diff --git a/src/app/CMakeLists.txt b/src/app/CMakeLists.txt
index 17db8f182..00425aa4e 100644
--- a/src/app/CMakeLists.txt
+++ b/src/app/CMakeLists.txt
@@ -233,7 +233,6 @@ add_library(app-lib
   document.cpp
   document_api.cpp
   document_exporter.cpp
-  document_location.cpp
   document_range.cpp
   document_range_ops.cpp
   document_undo.cpp
diff --git a/src/app/app.cpp b/src/app/app.cpp
index a94753a10..53be0beea 100644
--- a/src/app/app.cpp
+++ b/src/app/app.cpp
@@ -21,7 +21,6 @@
 #include "app/console.h"
 #include "app/crash/data_recovery.h"
 #include "app/document_exporter.h"
-#include "app/document_location.h"
 #include "app/document_undo.h"
 #include "app/file/file.h"
 #include "app/file/file_formats_manager.h"
@@ -65,6 +64,7 @@
 #include "doc/image.h"
 #include "doc/layer.h"
 #include "doc/palette.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 #include "render/render.h"
 #include "scripting/engine.h"
@@ -424,7 +424,7 @@ void App::initialize(const AppOptions& options)
 
           // Scale all sprites
           for (auto doc : ctx->documents()) {
-            ctx->setActiveDocument(doc);
+            ctx->setActiveDocument(static_cast<app::Document*>(doc));
             ctx->executeCommand(command);
           }
         }
@@ -664,9 +664,9 @@ void app_refresh_screen()
   Context* context = UIContext::instance();
   ASSERT(context != NULL);
 
-  DocumentLocation location = context->activeLocation();
+  Site site = context->activeSite();
 
-  if (Palette* pal = location.palette())
+  if (Palette* pal = site.palette())
     set_current_palette(pal, false);
   else
     set_current_palette(NULL, false);
diff --git a/src/app/cmd_transaction.cpp b/src/app/cmd_transaction.cpp
index 83ed15e33..a3f92c4c6 100644
--- a/src/app/cmd_transaction.cpp
+++ b/src/app/cmd_transaction.cpp
@@ -12,7 +12,7 @@
 #include "app/cmd_transaction.h"
 
 #include "app/context.h"
-#include "app/document_location.h"
+#include "doc/site.h"
 
 namespace app {
 
@@ -64,8 +64,8 @@ std::string CmdTransaction::onLabel() const
 
 doc::SpritePosition CmdTransaction::calcSpritePosition()
 {
-  app::DocumentLocation loc = context()->activeLocation();
-  return doc::SpritePosition(loc.layerIndex(), loc.frame());
+  doc::Site site = context()->activeSite();
+  return doc::SpritePosition(site.layerIndex(), site.frame());
 }
 
 } // namespace app
diff --git a/src/app/color_picker.cpp b/src/app/color_picker.cpp
index 5d09fd4ca..75167cd9c 100644
--- a/src/app/color_picker.cpp
+++ b/src/app/color_picker.cpp
@@ -11,10 +11,10 @@
 
 #include "app/color_picker.h"
 
-#include "app/document_location.h"
 #include "doc/cel.h"
 #include "doc/image.h"
 #include "doc/primitives.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 #include "gfx/point.h"
 #include "render/get_sprite_pixel.h"
@@ -27,7 +27,7 @@ ColorPicker::ColorPicker()
 {
 }
 
-void ColorPicker::pickColor(const DocumentLocation& location,
+void ColorPicker::pickColor(const doc::Site& site,
   const gfx::Point& pos, Mode mode)
 {
   m_alpha = 255;
@@ -36,17 +36,17 @@ void ColorPicker::pickColor(const DocumentLocation& location,
   // Get the color from the image
   if (mode == FromComposition) { // Pick from the composed image
     m_color = app::Color::fromImage(
-      location.sprite()->pixelFormat(),
-      render::get_sprite_pixel(location.sprite(), pos.x, pos.y, location.frame()));
+      site.sprite()->pixelFormat(),
+      render::get_sprite_pixel(site.sprite(), pos.x, pos.y, site.frame()));
 
     doc::CelList cels;
-    location.sprite()->pickCels(pos.x, pos.y, location.frame(), 128, cels);
+    site.sprite()->pickCels(pos.x, pos.y, site.frame(), 128, cels);
     if (!cels.empty())
       m_layer = cels.front()->layer();
   }
   else {                        // Pick from the current layer
     int u, v;
-    doc::Image* image = location.image(&u, &v, NULL);
+    doc::Image* image = site.image(&u, &v, NULL);
     gfx::Point pt(pos.x-u, pos.y-v);
 
     if (image && image->bounds().contains(pt)) {
@@ -62,7 +62,7 @@ void ColorPicker::pickColor(const DocumentLocation& location,
       }
 
       m_color = app::Color::fromImage(image->pixelFormat(), imageColor);
-      m_layer = const_cast<Layer*>(location.layer());
+      m_layer = const_cast<Layer*>(site.layer());
     }
   }
 }
diff --git a/src/app/color_picker.h b/src/app/color_picker.h
index 08e971e69..b390cc81e 100644
--- a/src/app/color_picker.h
+++ b/src/app/color_picker.h
@@ -13,8 +13,11 @@
 #include "doc/layer.h"
 #include "gfx/point.h"
 
+namespace doc {
+  class Site;
+}
+
 namespace app {
-  class DocumentLocation;
 
   class ColorPicker {
   public:
@@ -22,7 +25,7 @@ namespace app {
 
     ColorPicker();
 
-    void pickColor(const DocumentLocation& location,
+    void pickColor(const doc::Site& site,
       const gfx::Point& pos, Mode mode);
 
     app::Color color() const { return m_color; }
diff --git a/src/app/commands/cmd_background_from_layer.cpp b/src/app/commands/cmd_background_from_layer.cpp
index ef53f9a62..dc1ea1e9c 100644
--- a/src/app/commands/cmd_background_from_layer.cpp
+++ b/src/app/commands/cmd_background_from_layer.cpp
@@ -12,7 +12,6 @@
 #include "app/commands/command.h"
 #include "app/context_access.h"
 #include "app/document_api.h"
-#include "app/document_location.h"
 #include "app/modules/gui.h"
 #include "app/settings/settings.h"
 #include "app/ui/color_bar.h"
diff --git a/src/app/commands/cmd_clear.cpp b/src/app/commands/cmd_clear.cpp
index 133cfe84f..cc4d2f4e8 100644
--- a/src/app/commands/cmd_clear.cpp
+++ b/src/app/commands/cmd_clear.cpp
@@ -15,7 +15,6 @@
 #include "app/commands/command.h"
 #include "app/commands/commands.h"
 #include "app/context_access.h"
-#include "app/document_location.h"
 #include "app/modules/gui.h"
 #include "app/transaction.h"
 #include "app/ui/color_bar.h"
diff --git a/src/app/commands/cmd_clear_cel.cpp b/src/app/commands/cmd_clear_cel.cpp
index 82299c3d4..aac85336f 100644
--- a/src/app/commands/cmd_clear_cel.cpp
+++ b/src/app/commands/cmd_clear_cel.cpp
@@ -54,7 +54,7 @@ void ClearCelCommand::onExecute(Context* context)
   {
     Transaction transaction(writer.context(), "Clear Cel");
 
-    // TODO the range of selected frames should be in the DocumentLocation.
+    // TODO the range of selected frames should be in doc::Site.
     Timeline::Range range = App::instance()->getMainWindow()->getTimeline()->range();
     if (range.enabled()) {
       Sprite* sprite = writer.sprite();
diff --git a/src/app/commands/cmd_configure_tools.cpp b/src/app/commands/cmd_configure_tools.cpp
index ff8c2cf07..e2e86f58e 100644
--- a/src/app/commands/cmd_configure_tools.cpp
+++ b/src/app/commands/cmd_configure_tools.cpp
@@ -58,7 +58,7 @@ public:
     centerWindow();
     load_window_pos(this, "ConfigureTool");
 
-    onSetActiveDocument(m_ctx->activeDocument());
+    onActiveDocumentChange(m_ctx->activeDocument());
   }
 
   ~ToolsConfigurationWindow() {
@@ -79,7 +79,7 @@ private:
     return preferences().document(m_ctx->activeDocument());
   }
 
-  void onSetActiveDocument(doc::Document* document) override {
+  void onActiveDocumentChange(doc::Document* document) override {
     DocumentPreferences& docPref = this->docPref();
 
     tiled()->setSelected(docPref.tiled.mode() != filters::TiledMode::NONE);
diff --git a/src/app/commands/cmd_copy.cpp b/src/app/commands/cmd_copy.cpp
index 756573acd..640ed793c 100644
--- a/src/app/commands/cmd_copy.cpp
+++ b/src/app/commands/cmd_copy.cpp
@@ -12,11 +12,13 @@
 #include "app/app.h"
 #include "app/commands/command.h"
 #include "app/context_access.h"
+#include "app/document.h"
 #include "app/ui/main_window.h"
 #include "app/ui/timeline.h"
 #include "app/util/clipboard.h"
 #include "doc/layer.h"
 #include "doc/mask.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 #include "ui/base.h"
 
@@ -53,9 +55,9 @@ void CopyCommand::onExecute(Context* context)
   if (range.enabled()) {
     clipboard::copy_range(reader, range);
   }
-  else if (reader.location()->document() &&
-           reader.location()->document()->isMaskVisible() &&
-           reader.location()->image()) {
+  else if (reader.site()->document() &&
+           static_cast<const app::Document*>(reader.site()->document())->isMaskVisible() &&
+           reader.site()->image()) {
     clipboard::copy(reader);
   }
 }
diff --git a/src/app/commands/cmd_eyedropper.cpp b/src/app/commands/cmd_eyedropper.cpp
index c3350a9c3..a9ecd4f13 100644
--- a/src/app/commands/cmd_eyedropper.cpp
+++ b/src/app/commands/cmd_eyedropper.cpp
@@ -14,7 +14,6 @@
 #include "app/color_picker.h"
 #include "app/commands/command.h"
 #include "app/commands/params.h"
-#include "app/document_location.h"
 #include "app/modules/editors.h"
 #include "app/settings/settings.h"
 #include "app/tools/tool.h"
@@ -23,6 +22,7 @@
 #include "app/ui/editor/editor.h"
 #include "app/ui_context.h"
 #include "doc/image.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 #include "ui/manager.h"
 #include "ui/system.h"
@@ -80,7 +80,7 @@ void EyedropperCommand::onExecute(Context* context)
   bool grabAlpha = settings->getGrabAlpha();
 
   ColorPicker picker;
-  picker.pickColor(editor->getDocumentLocation(),
+  picker.pickColor(editor->getSite(),
     pixelPos,
     grabAlpha ?
     ColorPicker::FromActiveLayer:
diff --git a/src/app/commands/cmd_flip.cpp b/src/app/commands/cmd_flip.cpp
index e213bd5cf..685b496da 100644
--- a/src/app/commands/cmd_flip.cpp
+++ b/src/app/commands/cmd_flip.cpp
@@ -79,7 +79,7 @@ void FlipCommand::onExecute(Context* context)
       Mask* mask = document->mask();
       CelList cels;
 
-      DocumentLocation loc = *writer.location();
+      Site site = *writer.site();
       DocumentRange range = App::instance()->getMainWindow()->getTimeline()->range();
       if (range.enabled())
         cels = get_unique_cels(sprite, range);
@@ -87,11 +87,11 @@ void FlipCommand::onExecute(Context* context)
         cels.push_back(writer.cel());
 
       for (Cel* cel : cels) {
-        loc.frame(cel->frame());
-        loc.layer(cel->layer());
+        site.frame(cel->frame());
+        site.layer(cel->layer());
 
         int x, y;
-        Image* image = loc.image(&x, &y);
+        Image* image = site.image(&x, &y);
         if (!image)
           continue;
 
diff --git a/src/app/commands/cmd_frame_properties.cpp b/src/app/commands/cmd_frame_properties.cpp
index 90d4c5d89..2bf2d1a93 100644
--- a/src/app/commands/cmd_frame_properties.cpp
+++ b/src/app/commands/cmd_frame_properties.cpp
@@ -95,7 +95,7 @@ void FramePropertiesCommand::onExecute(Context* context)
       break;
 
     case CURRENT_RANGE: {
-      // TODO the range of selected frames should be in the DocumentLocation.
+      // TODO the range of selected frames should be in doc::Site.
       Timeline::Range range = App::instance()->getMainWindow()->getTimeline()->range();
       if (range.enabled()) {
         firstFrame = range.frameBegin();
diff --git a/src/app/commands/cmd_goto_layer.cpp b/src/app/commands/cmd_goto_layer.cpp
index 9c77251b4..c40bb9fca 100644
--- a/src/app/commands/cmd_goto_layer.cpp
+++ b/src/app/commands/cmd_goto_layer.cpp
@@ -28,11 +28,11 @@ public:
   }
 
 protected:
-  void updateStatusBar(DocumentLocation& location) {
-    if (location.layer() != NULL)
+  void updateStatusBar(Site& site) {
+    if (site.layer() != NULL)
       StatusBar::instance()
         ->setStatusText(1000, "Layer `%s' selected",
-          location.layer()->name().c_str());
+          site.layer()->name().c_str());
   }
 };
 
@@ -63,19 +63,19 @@ void GotoPreviousLayerCommand::onExecute(Context* context)
 {
   const ContextReader reader(context);
   const Sprite* sprite = reader.sprite();
-  DocumentLocation location = *reader.location();
+  Site site = *reader.site();
 
-  if (location.layerIndex() > 0)
-    location.layerIndex(location.layerIndex().previous());
+  if (site.layerIndex() > 0)
+    site.layerIndex(site.layerIndex().previous());
   else
-    location.layerIndex(LayerIndex(sprite->countLayers()-1));
+    site.layerIndex(LayerIndex(sprite->countLayers()-1));
 
   // Flash the current layer
   ASSERT(current_editor != NULL && "Current editor cannot be null when we have a current sprite");
-  current_editor->setLayer(location.layer());
+  current_editor->setLayer(site.layer());
   current_editor->flashCurrentLayer();
 
-  updateStatusBar(location);
+  updateStatusBar(site);
 }
 
 class GotoNextLayerCommand : public GotoCommand {
@@ -105,19 +105,19 @@ void GotoNextLayerCommand::onExecute(Context* context)
 {
   const ContextReader reader(context);
   const Sprite* sprite = reader.sprite();
-  DocumentLocation location = *reader.location();
+  Site site = *reader.site();
 
-  if (location.layerIndex() < sprite->countLayers()-1)
-    location.layerIndex(location.layerIndex().next());
+  if (site.layerIndex() < sprite->countLayers()-1)
+    site.layerIndex(site.layerIndex().next());
   else
-    location.layerIndex(LayerIndex(0));
+    site.layerIndex(LayerIndex(0));
 
   // Flash the current layer
   ASSERT(current_editor != NULL && "Current editor cannot be null when we have a current sprite");
-  current_editor->setLayer(location.layer());
+  current_editor->setLayer(site.layer());
   current_editor->flashCurrentLayer();
 
-  updateStatusBar(location);
+  updateStatusBar(site);
 }
 
 Command* CommandFactory::createGotoPreviousLayerCommand()
diff --git a/src/app/commands/cmd_import_sprite_sheet.cpp b/src/app/commands/cmd_import_sprite_sheet.cpp
index 62227480c..c81bd8398 100644
--- a/src/app/commands/cmd_import_sprite_sheet.cpp
+++ b/src/app/commands/cmd_import_sprite_sheet.cpp
@@ -257,7 +257,7 @@ retry:;
 
   try {
     Sprite* sprite = document->sprite();
-    frame_t currentFrame = context->activeLocation().frame();
+    frame_t currentFrame = context->activeSite().frame();
     render::Render render;
 
     // As first step, we cut each tile and add them into "animation" list.
diff --git a/src/app/commands/cmd_mask_content.cpp b/src/app/commands/cmd_mask_content.cpp
index 5ce6a8512..22238ea98 100644
--- a/src/app/commands/cmd_mask_content.cpp
+++ b/src/app/commands/cmd_mask_content.cpp
@@ -64,7 +64,7 @@ void MaskContentCommand::onExecute(Context* context)
   gfx::Color color;
   if (writer.layer()->isBackground()) {
     ColorPicker picker;
-    picker.pickColor(*writer.location(), gfx::Point(0, 0), ColorPicker::FromComposition);
+    picker.pickColor(*writer.site(), gfx::Point(0, 0), ColorPicker::FromComposition);
     color = color_utils::color_for_layer(picker.color(), writer.layer());
   }
   else
diff --git a/src/app/commands/cmd_new_frame.cpp b/src/app/commands/cmd_new_frame.cpp
index ff1613ad7..ca6707795 100644
--- a/src/app/commands/cmd_new_frame.cpp
+++ b/src/app/commands/cmd_new_frame.cpp
@@ -116,7 +116,7 @@ void NewFrameCommand::onExecute(Context* context)
 
   StatusBar::instance()
     ->showTip(1000, "New frame %d/%d",
-              (int)context->activeLocation().frame()+1,
+              (int)context->activeSite().frame()+1,
               (int)sprite->totalFrames());
 
   App::instance()->getMainWindow()->popTimeline();
diff --git a/src/app/commands/cmd_remove_frame.cpp b/src/app/commands/cmd_remove_frame.cpp
index 916e2e8ab..6507bdfcc 100644
--- a/src/app/commands/cmd_remove_frame.cpp
+++ b/src/app/commands/cmd_remove_frame.cpp
@@ -57,7 +57,7 @@ void RemoveFrameCommand::onExecute(Context* context)
     Transaction transaction(writer.context(), "Remove Frame");
     DocumentApi api = document->getApi(transaction);
 
-    // TODO the range of selected frames should be in the DocumentLocation.
+    // TODO the range of selected frames should be in doc::Site.
     Timeline::Range range = App::instance()->getMainWindow()->getTimeline()->range();
     if (range.enabled()) {
       for (frame_t frame = range.frameEnd(),
diff --git a/src/app/commands/cmd_remove_layer.cpp b/src/app/commands/cmd_remove_layer.cpp
index 33a6277df..175054b20 100644
--- a/src/app/commands/cmd_remove_layer.cpp
+++ b/src/app/commands/cmd_remove_layer.cpp
@@ -62,7 +62,7 @@ void RemoveLayerCommand::onExecute(Context* context)
     Transaction transaction(writer.context(), "Remove Layer");
     DocumentApi api = document->getApi(transaction);
 
-    // TODO the range of selected layer should be in the DocumentLocation.
+    // TODO the range of selected layer should be in doc::Site.
     Timeline::Range range = App::instance()->getMainWindow()->getTimeline()->range();
     if (range.enabled()) {
       if (range.layers() == sprite->countLayers()) {
diff --git a/src/app/commands/cmd_undo.cpp b/src/app/commands/cmd_undo.cpp
index d460a9f17..984c65d08 100644
--- a/src/app/commands/cmd_undo.cpp
+++ b/src/app/commands/cmd_undo.cpp
@@ -70,8 +70,8 @@ void UndoCommand::onExecute(Context* context)
     App::instance()->preferences().undo.gotoModified();
 
   if (gotoModified) {
-    SpritePosition currentPosition(writer.location()->layerIndex(),
-                                   writer.location()->frame());
+    SpritePosition currentPosition(writer.site()->layerIndex(),
+                                   writer.site()->frame());
 
     if (m_type == Undo)
       spritePosition = undo->nextUndoSpritePosition();
@@ -113,8 +113,8 @@ void UndoCommand::onExecute(Context* context)
   // weren't able to reach before the undo).
   if (gotoModified) {
     SpritePosition currentPosition(
-      writer.location()->layerIndex(),
-      writer.location()->frame());
+      writer.site()->layerIndex(),
+      writer.site()->frame());
 
     if (spritePosition != currentPosition) {
       current_editor->setLayer(sprite->indexToLayer(spritePosition.layerIndex()));
diff --git a/src/app/commands/cmd_unlink_cel.cpp b/src/app/commands/cmd_unlink_cel.cpp
index 11c6a4047..47a8e6042 100644
--- a/src/app/commands/cmd_unlink_cel.cpp
+++ b/src/app/commands/cmd_unlink_cel.cpp
@@ -54,7 +54,7 @@ void UnlinkCelCommand::onExecute(Context* context)
   {
     Transaction transaction(writer.context(), "Unlink Cel");
 
-    // TODO the range of selected frames should be in the DocumentLocation.
+    // TODO the range of selected frames should be in doc::Site.
     Timeline::Range range = App::instance()->getMainWindow()->getTimeline()->range();
     if (range.enabled()) {
       Sprite* sprite = writer.sprite();
diff --git a/src/app/commands/filters/cmd_replace_color.cpp b/src/app/commands/filters/cmd_replace_color.cpp
index a59e54210..6b774047e 100644
--- a/src/app/commands/filters/cmd_replace_color.cpp
+++ b/src/app/commands/filters/cmd_replace_color.cpp
@@ -27,6 +27,7 @@
 #include "filters/replace_color_filter.h"
 #include "doc/image.h"
 #include "doc/mask.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 #include "ui/ui.h"
 
@@ -134,9 +135,9 @@ bool ReplaceColorCommand::onEnabled(Context* context)
 
 void ReplaceColorCommand::onExecute(Context* context)
 {
-  DocumentLocation location = context->activeLocation();
+  Site site = context->activeSite();
 
-  ReplaceColorFilterWrapper filter(location.layer());
+  ReplaceColorFilterWrapper filter(site.layer());
   filter.setFrom(get_config_color(ConfigSection, "Color1", ColorBar::instance()->getFgColor()));
   filter.setTo(get_config_color(ConfigSection, "Color2", ColorBar::instance()->getBgColor()));
   filter.setTolerance(get_config_int(ConfigSection, "Tolerance", 0));
diff --git a/src/app/commands/filters/filter_manager_impl.cpp b/src/app/commands/filters/filter_manager_impl.cpp
index d6184d961..d32b755da 100644
--- a/src/app/commands/filters/filter_manager_impl.cpp
+++ b/src/app/commands/filters/filter_manager_impl.cpp
@@ -14,6 +14,7 @@
 #include "app/cmd/copy_rect.h"
 #include "app/cmd/unlink_cel.h"
 #include "app/context_access.h"
+#include "app/document.h"
 #include "app/ini_file.h"
 #include "app/modules/editors.h"
 #include "app/transaction.h"
@@ -23,6 +24,7 @@
 #include "doc/images_collector.h"
 #include "doc/layer.h"
 #include "doc/mask.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 #include "filters/filter.h"
 #include "ui/manager.h"
@@ -40,7 +42,7 @@ using namespace ui;
 
 FilterManagerImpl::FilterManagerImpl(Context* context, Filter* filter)
   : m_context(context)
-  , m_location(context->activeLocation())
+  , m_site(context->activeSite())
   , m_filter(filter)
   , m_dst(NULL)
   , m_preview_mask(NULL)
@@ -56,17 +58,22 @@ FilterManagerImpl::FilterManagerImpl(Context* context, Filter* filter)
   m_targetOrig = TARGET_ALL_CHANNELS;
   m_target = TARGET_ALL_CHANNELS;
 
-  Image* image = m_location.image(&offset_x, &offset_y);
+  Image* image = m_site.image(&offset_x, &offset_y);
   if (image == NULL)
     throw NoImageException();
 
-  init(m_location.layer(), image, offset_x, offset_y);
+  init(m_site.layer(), image, offset_x, offset_y);
 }
 
 FilterManagerImpl::~FilterManagerImpl()
 {
 }
 
+app::Document* FilterManagerImpl::document()
+{
+  return static_cast<app::Document*>(m_site.document());
+}
+
 void FilterManagerImpl::setProgressDelegate(IProgressDelegate* progressDelegate)
 {
   m_progressDelegate = progressDelegate;
@@ -74,7 +81,7 @@ void FilterManagerImpl::setProgressDelegate(IProgressDelegate* progressDelegate)
 
 PixelFormat FilterManagerImpl::pixelFormat() const
 {
-  return m_location.sprite()->pixelFormat();
+  return m_site.sprite()->pixelFormat();
 }
 
 void FilterManagerImpl::setTarget(int target)
@@ -83,14 +90,14 @@ void FilterManagerImpl::setTarget(int target)
   m_target = target;
 
   // The alpha channel of the background layer can't be modified.
-  if (m_location.layer() &&
-      m_location.layer()->isBackground())
+  if (m_site.layer() &&
+      m_site.layer()->isBackground())
     m_target &= ~TARGET_ALPHA_CHANNEL;
 }
 
 void FilterManagerImpl::begin()
 {
-  Document* document = m_location.document();
+  Document* document = static_cast<app::Document*>(m_site.document());
 
   m_row = 0;
   m_mask = (document->isMaskVisible() ? document->mask(): NULL);
@@ -100,7 +107,7 @@ void FilterManagerImpl::begin()
 
 void FilterManagerImpl::beginForPreview()
 {
-  Document* document = m_location.document();
+  Document* document = static_cast<app::Document*>(m_site.document());
 
   if (document->isMaskVisible())
     m_preview_mask.reset(new Mask(*document->mask()));
@@ -117,7 +124,7 @@ void FilterManagerImpl::beginForPreview()
 
   {
     Editor* editor = current_editor;
-    Sprite* sprite = m_location.sprite();
+    Sprite* sprite = m_site.sprite();
     gfx::Rect vp = View::getView(editor)->getViewportBounds();
     vp = editor->screenToEditor(vp);
     vp = vp.createIntersect(sprite->bounds());
@@ -162,7 +169,7 @@ bool FilterManagerImpl::applyStep()
     m_maskIterator = m_maskBits.begin();
   }
 
-  switch (m_location.sprite()->pixelFormat()) {
+  switch (m_site.sprite()->pixelFormat()) {
     case IMAGE_RGB:       m_filter->applyToRgba(this); break;
     case IMAGE_GRAYSCALE: m_filter->applyToGrayscale(this); break;
     case IMAGE_INDEXED:   m_filter->applyToIndexed(this); break;
@@ -199,9 +206,9 @@ void FilterManagerImpl::applyToTarget()
   bool cancelled = false;
 
   ImagesCollector images((m_target & TARGET_ALL_LAYERS ?
-                          m_location.sprite()->folder():
-                          m_location.layer()),
-                         m_location.frame(),
+                          m_site.sprite()->folder():
+                          m_site.layer()),
+                         m_site.frame(),
                          (m_target & TARGET_ALL_FRAMES) == TARGET_ALL_FRAMES,
                          true); // we will write in each image
   if (images.empty())
@@ -289,12 +296,12 @@ bool FilterManagerImpl::skipPixel()
 
 Palette* FilterManagerImpl::getPalette()
 {
-  return m_location.sprite()->palette(m_location.frame());
+  return m_site.sprite()->palette(m_site.frame());
 }
 
 RgbMap* FilterManagerImpl::getRgbMap()
 {
-  return m_location.sprite()->rgbMap(m_location.frame());
+  return m_site.sprite()->rgbMap(m_site.frame());
 }
 
 void FilterManagerImpl::init(const Layer* layer, Image* image, int offset_x, int offset_y)
@@ -302,7 +309,7 @@ void FilterManagerImpl::init(const Layer* layer, Image* image, int offset_x, int
   m_offset_x = offset_x;
   m_offset_y = offset_y;
 
-  if (!updateMask(m_location.document()->mask(), image))
+  if (!updateMask(static_cast<app::Document*>(m_site.document())->mask(), image))
     throw InvalidAreaException();
 
   m_src = image;
diff --git a/src/app/commands/filters/filter_manager_impl.h b/src/app/commands/filters/filter_manager_impl.h
index e240d3219..2d56df9bc 100644
--- a/src/app/commands/filters/filter_manager_impl.h
+++ b/src/app/commands/filters/filter_manager_impl.h
@@ -9,14 +9,14 @@
 #define APP_COMMANDS_FILTERS_FILTER_MANAGER_IMPL_H_INCLUDED
 #pragma once
 
-#include "app/document_location.h"
 #include "base/exception.h"
 #include "base/unique_ptr.h"
-#include "filters/filter_indexed_data.h"
-#include "filters/filter_manager.h"
 #include "doc/image_bits.h"
 #include "doc/image_traits.h"
 #include "doc/pixel_format.h"
+#include "doc/site.h"
+#include "filters/filter_indexed_data.h"
+#include "filters/filter_manager.h"
 
 #include <cstring>
 
@@ -72,7 +72,7 @@ namespace app {
 
     void setProgressDelegate(IProgressDelegate* progressDelegate);
 
-    PixelFormat pixelFormat() const;
+    doc::PixelFormat pixelFormat() const;
 
     void setTarget(Target target);
 
@@ -82,11 +82,11 @@ namespace app {
     bool applyStep();
     void applyToTarget();
 
-    Document* document() { return m_location.document(); }
-    Sprite* sprite() { return m_location.sprite(); }
-    Layer* layer() { return m_location.layer(); }
-    frame_t frame() { return m_location.frame(); }
-    Image* destinationImage() const { return m_dst; }
+    app::Document* document();
+    doc::Sprite* sprite() { return m_site.sprite(); }
+    doc::Layer* layer() { return m_site.layer(); }
+    doc::frame_t frame() { return m_site.frame(); }
+    doc::Image* destinationImage() const { return m_dst; }
 
     // Updates the current editor to show the progress of the preview.
     void flush();
@@ -98,30 +98,30 @@ namespace app {
     Target getTarget() { return m_target; }
     FilterIndexedData* getIndexedData() { return this; }
     bool skipPixel();
-    const Image* getSourceImage() { return m_src; }
+    const doc::Image* getSourceImage() { return m_src; }
     int x() { return m_x; }
     int y() { return m_y+m_row; }
 
     // FilterIndexedData implementation
-    Palette* getPalette();
-    RgbMap* getRgbMap();
+    doc::Palette* getPalette();
+    doc::RgbMap* getRgbMap();
 
   private:
-    void init(const Layer* layer, Image* image, int offset_x, int offset_y);
+    void init(const doc::Layer* layer, doc::Image* image, int offset_x, int offset_y);
     void apply(Transaction& transaction);
-    void applyToImage(Transaction& transaction, Layer* layer, Image* image, int x, int y);
-    bool updateMask(Mask* mask, const Image* image);
+    void applyToImage(Transaction& transaction, doc::Layer* layer, doc::Image* image, int x, int y);
+    bool updateMask(doc::Mask* mask, const doc::Image* image);
 
     Context* m_context;
-    DocumentLocation m_location;
+    doc::Site m_site;
     Filter* m_filter;
-    Image* m_src;
-    base::UniquePtr<Image> m_dst;
+    doc::Image* m_src;
+    base::UniquePtr<doc::Image> m_dst;
     int m_row;
     int m_x, m_y, m_w, m_h;
     int m_offset_x, m_offset_y;
-    Mask* m_mask;
-    base::UniquePtr<Mask> m_preview_mask;
+    doc::Mask* m_mask;
+    base::UniquePtr<doc::Mask> m_preview_mask;
     doc::ImageBits<doc::BitmapTraits> m_maskBits;
     doc::ImageBits<doc::BitmapTraits>::iterator m_maskIterator;
     Target m_targetOrig;          // Original targets
diff --git a/src/app/context.cpp b/src/app/context.cpp
index c3d3cfded..4e2ab8454 100644
--- a/src/app/context.cpp
+++ b/src/app/context.cpp
@@ -16,7 +16,6 @@
 #include "app/commands/commands.h"
 #include "app/console.h"
 #include "app/document.h"
-#include "app/document_location.h"
 #include "app/settings/settings.h"
 
 #include <algorithm>
@@ -52,14 +51,6 @@ app::Document* Context::activeDocument() const
   return static_cast<app::Document*>(doc::Context::activeDocument());
 }
 
-DocumentLocation Context::activeLocation() const
-{
-  DocumentLocation location;
-  onGetActiveLocation(&location);
-  ASSERT(location.document() == doc::Context::activeDocument());
-  return location;
-}
-
 void Context::executeCommand(const char* commandName)
 {
   Command* cmd = CommandsModule::instance()->getCommandByName(commandName);
@@ -124,9 +115,4 @@ void Context::onCreateDocument(doc::CreateDocumentArgs* args)
   args->setDocument(new app::Document(NULL));
 }
 
-void Context::onGetActiveLocation(DocumentLocation* location) const
-{
-  // Without active location
-}
-
 } // namespace app
diff --git a/src/app/context.h b/src/app/context.h
index 3ca6ffc99..f740698b9 100644
--- a/src/app/context.h
+++ b/src/app/context.h
@@ -21,7 +21,6 @@
 namespace app {
   class Command;
   class Document;
-  class DocumentLocation;
   class ISettings;
 
   class CommandPreconditionException : public base::Exception {
@@ -50,7 +49,6 @@ namespace app {
     void sendDocumentToTop(doc::Document* document);
 
     app::Document* activeDocument() const;
-    DocumentLocation activeLocation() const;
 
     void executeCommand(const char* commandName);
     virtual void executeCommand(Command* command, const Params& params = Params());
@@ -60,7 +58,6 @@ namespace app {
 
   protected:
     virtual void onCreateDocument(doc::CreateDocumentArgs* args) override;
-    virtual void onGetActiveLocation(DocumentLocation* location) const;
 
   private:
     // Settings in this context.
diff --git a/src/app/context_access.h b/src/app/context_access.h
index 78ad8847c..365a3de3b 100644
--- a/src/app/context_access.h
+++ b/src/app/context_access.h
@@ -10,7 +10,7 @@
 #pragma once
 
 #include "app/document_access.h"
-#include "app/document_location.h"
+#include "doc/site.h"
 
 namespace app {
 
@@ -20,35 +20,35 @@ namespace app {
   class ContextAccess {
   public:
     const Context* context() const { return m_context; }
-    const DocumentLocation* location() const { return &m_location; }
+    const Site* site() const { return &m_site; }
     const DocumentAccessT& document() const { return m_document; }
-    const Sprite* sprite() const { return m_location.sprite(); }
-    const Layer* layer() const { return m_location.layer(); }
-    frame_t frame() const { return m_location.frame(); }
-    const Cel* cel() const { return m_location.cel(); }
+    const Sprite* sprite() const { return m_site.sprite(); }
+    const Layer* layer() const { return m_site.layer(); }
+    frame_t frame() const { return m_site.frame(); }
+    const Cel* cel() const { return m_site.cel(); }
 
-    // You cannot change the location directly from a writable ContextAccess anyway.
-    const DocumentLocation* location() { return &m_location; }
+    // You cannot change the site directly from a writable ContextAccess anyway.
+    const Site* site() { return &m_site; }
 
     Context* context() { return const_cast<Context*>(m_context); }
     DocumentAccessT& document() { return m_document; }
-    Sprite* sprite() { return m_location.sprite(); }
-    Layer* layer() { return m_location.layer(); }
-    Cel* cel() { return m_location.cel(); }
+    Sprite* sprite() { return m_site.sprite(); }
+    Layer* layer() { return m_site.layer(); }
+    Cel* cel() { return m_site.cel(); }
 
     Image* image(int* x = NULL, int* y = NULL, int* opacity = NULL) const {
-      return m_location.image(x, y, opacity);
+      return m_site.image(x, y, opacity);
     }
 
     Palette* palette() const {
-      return m_location.palette();
+      return m_site.palette();
     }
 
   protected:
     ContextAccess(const Context* context, int timeout)
       : m_context(context)
       , m_document(context->activeDocument(), timeout)
-      , m_location(context->activeLocation())
+      , m_site(context->activeSite())
     {
     }
 
@@ -56,14 +56,14 @@ namespace app {
     ContextAccess(const Context* context, const DocumentReaderT& documentReader, int timeout)
       : m_context(context)
       , m_document(documentReader, timeout)
-      , m_location(context->activeLocation())
+      , m_site(context->activeSite())
     {
     }
 
   private:
     const Context* m_context;
     DocumentAccessT m_document;
-    DocumentLocation m_location;
+    Site m_site;
   };
 
   // You can use this class to access to the given context to read the
diff --git a/src/app/context_flags.cpp b/src/app/context_flags.cpp
index bf3f01e8c..7cf783558 100644
--- a/src/app/context_flags.cpp
+++ b/src/app/context_flags.cpp
@@ -13,9 +13,9 @@
 
 #include "app/context.h"
 #include "app/document.h"
-#include "app/document_location.h"
 #include "doc/cel.h"
 #include "doc/layer.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 
 namespace app {
@@ -27,8 +27,8 @@ ContextFlags::ContextFlags()
 
 void ContextFlags::update(Context* context)
 {
-  DocumentLocation location = context->activeLocation();
-  Document* document = location.document();
+  Site site = context->activeSite();
+  Document* document = static_cast<Document*>(site.document());
 
   m_flags = 0;
 
@@ -41,14 +41,14 @@ void ContextFlags::update(Context* context)
       if (document->isMaskVisible())
         m_flags |= HasVisibleMask;
 
-      Sprite* sprite = location.sprite();
+      Sprite* sprite = site.sprite();
       if (sprite) {
         m_flags |= HasActiveSprite;
 
         if (sprite->backgroundLayer())
           m_flags |= HasBackgroundLayer;
 
-        Layer* layer = location.layer();
+        Layer* layer = site.layer();
         if (layer) {
           m_flags |= HasActiveLayer;
 
@@ -64,7 +64,7 @@ void ContextFlags::update(Context* context)
           if (layer->isImage()) {
             m_flags |= ActiveLayerIsImage;
 
-            Cel* cel = layer->cel(location.frame());
+            Cel* cel = layer->cel(site.frame());
             if (cel) {
               m_flags |= HasActiveCel;
 
diff --git a/src/app/document_api_tests.cpp b/src/app/document_api_tests.cpp
index bed78d16c..56b852c31 100644
--- a/src/app/document_api_tests.cpp
+++ b/src/app/document_api_tests.cpp
@@ -7,13 +7,15 @@
 
 #include "tests/test.h"
 
+#include "app/context.h"
+#include "app/document.h"
 #include "app/document_api.h"
-#include "app/test_context.h"
 #include "app/transaction.h"
 #include "base/unique_ptr.h"
 #include "doc/cel.h"
 #include "doc/image.h"
 #include "doc/primitives.h"
+#include "doc/test_context.h"
 
 using namespace app;
 using namespace doc;
@@ -21,7 +23,7 @@ using namespace doc;
 typedef base::UniquePtr<app::Document> DocumentPtr;
 
 TEST(DocumentApi, MoveCel) {
-  TestContext ctx;
+  TestContextT<app::Context> ctx;
   DocumentPtr doc(static_cast<app::Document*>(ctx.documents().add(32, 16)));
   Sprite* sprite = doc->sprite();
   LayerImage* layer1 = dynamic_cast<LayerImage*>(sprite->folder()->getFirstLayer());
diff --git a/src/app/document_range_tests.cpp b/src/app/document_range_tests.cpp
index 528ad98e4..d8b5deae3 100644
--- a/src/app/document_range_tests.cpp
+++ b/src/app/document_range_tests.cpp
@@ -7,15 +7,16 @@
 
 #include "tests/test.h"
 
+#include "app/context.h"
 #include "app/document.h"
 #include "app/document_api.h"
 #include "app/document_range.h"
 #include "app/document_range_ops.h"
 #include "app/document_undo.h"
-#include "app/test_context.h"
 #include "app/transaction.h"
 #include "base/unique_ptr.h"
 #include "doc/doc.h"
+#include "doc/test_context.h"
 
 using namespace app;
 using namespace doc;
@@ -181,7 +182,7 @@ protected:
     return (cel == NULL);
   }
 
-  TestContext ctx;
+  TestContextT<app::Context> ctx;
   DocumentPtr doc;
   Sprite* sprite;
   LayerImage* layer1;
diff --git a/src/app/file/gif_tests.cpp b/src/app/file/gif_tests.cpp
index 20dc50eaf..5301c2ca8 100644
--- a/src/app/file/gif_tests.cpp
+++ b/src/app/file/gif_tests.cpp
@@ -12,8 +12,8 @@
 #include "app/file/file.h"
 #include "app/file/file_formats_manager.h"
 #include "app/file/gif_options.h"
-#include "app/test_context.h"
 #include "doc/doc.h"
+#include "doc/test_context.h"
 #include "she/scoped_handle.h"
 #include "she/system.h"
 
@@ -26,7 +26,7 @@ public:
   }
 
 protected:
-  app::TestContext m_ctx;
+  doc::TestContextT<app::Context> m_ctx;
   she::ScopedHandle<she::System> m_system;
 };
 
diff --git a/src/app/modules/gui.cpp b/src/app/modules/gui.cpp
index 98b13577c..4c24aeafd 100644
--- a/src/app/modules/gui.cpp
+++ b/src/app/modules/gui.cpp
@@ -15,7 +15,6 @@
 #include "app/commands/params.h"
 #include "app/console.h"
 #include "app/document.h"
-#include "app/document_location.h"
 #include "app/ini_file.h"
 #include "app/modules/editors.h"
 #include "app/modules/gfx.h"
diff --git a/src/app/test_context.h b/src/app/test_context.h
deleted file mode 100644
index 12adfc59c..000000000
--- a/src/app/test_context.h
+++ /dev/null
@@ -1,40 +0,0 @@
-// Aseprite
-// Copyright (C) 2001-2015  David Capello
-//
-// This program is free software; you can redistribute it and/or modify
-// it under the terms of the GNU General Public License version 2 as
-// published by the Free Software Foundation.
-
-#ifndef APP_TEST_CONTEXT_H_INCLUDED
-#define APP_TEST_CONTEXT_H_INCLUDED
-#pragma once
-
-#include "app/context.h"
-#include "app/document.h"
-#include "app/document_location.h"
-#include "doc/layer.h"
-#include "doc/sprite.h"
-
-namespace app {
-
-  class TestContext : public app::Context {
-  public:
-    TestContext() : app::Context(NULL) {
-    }
-
-  protected:
-    void onGetActiveLocation(DocumentLocation* location) const override {
-      Document* doc = activeDocument();
-      if (!doc)
-        return;
-
-      location->document(doc);
-      location->sprite(doc->sprite());
-      location->layer(doc->sprite()->folder()->getFirstLayer());
-      location->frame(0);
-    }
-  };
-
-} // namespace app
-
-#endif
diff --git a/src/app/transaction.cpp b/src/app/transaction.cpp
index 2498fa64c..a52b9e18d 100644
--- a/src/app/transaction.cpp
+++ b/src/app/transaction.cpp
@@ -25,9 +25,7 @@ Transaction::Transaction(Context* ctx, const std::string& label, Modification mo
   : m_ctx(ctx)
   , m_cmds(NULL)
 {
-  DocumentLocation location = m_ctx->activeLocation();
-
-  m_undo = location.document()->undoHistory();
+  m_undo = m_ctx->activeDocument()->undoHistory();
   m_cmds = new CmdTransaction(label,
     modification == Modification::ModifyDocument,
     m_undo->savedCounter());
diff --git a/src/app/ui/color_bar.cpp b/src/app/ui/color_bar.cpp
index b68dad9d8..7f177079c 100644
--- a/src/app/ui/color_bar.cpp
+++ b/src/app/ui/color_bar.cpp
@@ -195,7 +195,7 @@ void ColorBar::setPaletteEditorButtonState(bool state)
   m_paletteButton.setSelected(state);
 }
 
-void ColorBar::onSetActiveDocument(doc::Document* document)
+void ColorBar::onActiveDocumentChange(doc::Document* document)
 {
   destroyRemap();
 }
diff --git a/src/app/ui/color_bar.h b/src/app/ui/color_bar.h
index 73dd09d7c..99a6631c0 100644
--- a/src/app/ui/color_bar.h
+++ b/src/app/ui/color_bar.h
@@ -51,7 +51,7 @@ namespace app {
     void setPaletteEditorButtonState(bool state);
 
     // ContextObserver impl
-    void onSetActiveDocument(doc::Document* document) override;
+    void onActiveDocumentChange(doc::Document* document) override;
 
     // Signals
     Signal1<void, const app::Color&> FgColorChange;
diff --git a/src/app/ui/color_button.cpp b/src/app/ui/color_button.cpp
index 8d874d255..8e1add6a1 100644
--- a/src/app/ui/color_button.cpp
+++ b/src/app/ui/color_button.cpp
@@ -13,7 +13,6 @@
 #include "app/color.h"
 #include "app/color_picker.h"
 #include "app/color_utils.h"
-#include "app/document_location.h"
 #include "app/modules/gfx.h"
 #include "app/modules/gui.h"
 #include "app/ui/color_bar.h"
@@ -22,6 +21,7 @@
 #include "app/ui/editor/editor.h"
 #include "app/ui/skin/skin_theme.h"
 #include "app/ui/status_bar.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 #include "ui/preferred_size_event.h"
 #include "ui/ui.h"
@@ -120,12 +120,12 @@ bool ColorButton::onProcessMessage(Message* msg)
           // Pick a color from a editor
           else if (picked->type == editor_type()) {
             Editor* editor = static_cast<Editor*>(picked);
-            DocumentLocation location = editor->getDocumentLocation();
-            if (location.sprite()) {
+            Site site = editor->getSite();
+            if (site.sprite()) {
               gfx::Point editorPos = editor->screenToEditor(mousePos);
 
               ColorPicker picker;
-              picker.pickColor(location, editorPos, ColorPicker::FromComposition);
+              picker.pickColor(site, editorPos, ColorPicker::FromComposition);
               color = picker.color();
             }
           }
diff --git a/src/app/ui/document_view.cpp b/src/app/ui/document_view.cpp
index 322be0339..f8fabcc60 100644
--- a/src/app/ui/document_view.cpp
+++ b/src/app/ui/document_view.cpp
@@ -208,9 +208,9 @@ DocumentView::~DocumentView()
   delete m_editor;
 }
 
-void DocumentView::getDocumentLocation(DocumentLocation* location) const
+void DocumentView::getSite(Site* site) const
 {
-  m_editor->getDocumentLocation(location);
+  m_editor->getSite(site);
 }
 
 std::string DocumentView::getTabText()
diff --git a/src/app/ui/document_view.h b/src/app/ui/document_view.h
index 40e6b59ac..a10840d06 100644
--- a/src/app/ui/document_view.h
+++ b/src/app/ui/document_view.h
@@ -14,13 +14,16 @@
 #include "doc/document_observer.h"
 #include "ui/box.h"
 
+namespace doc {
+  class Site;
+}
+
 namespace ui {
   class View;
 }
 
 namespace app {
   class Document;
-  class DocumentLocation;
   class Editor;
 
   class DocumentView : public ui::Box
@@ -37,7 +40,7 @@ namespace app {
     ~DocumentView();
 
     Document* getDocument() const { return m_document; }
-    void getDocumentLocation(DocumentLocation* location) const;
+    void getSite(doc::Site* site) const;
     Editor* getEditor() { return m_editor; }
 
     bool isPreview() { return m_type == Preview; }
diff --git a/src/app/ui/editor/editor.cpp b/src/app/ui/editor/editor.cpp
index 9b4d6336d..48a672d40 100644
--- a/src/app/ui/editor/editor.cpp
+++ b/src/app/ui/editor/editor.cpp
@@ -17,7 +17,6 @@
 #include "app/commands/commands.h"
 #include "app/commands/params.h"
 #include "app/console.h"
-#include "app/document_location.h"
 #include "app/ini_file.h"
 #include "app/modules/gfx.h"
 #include "app/modules/gui.h"
@@ -269,19 +268,19 @@ void Editor::setFrame(frame_t frame)
   }
 }
 
-void Editor::getDocumentLocation(DocumentLocation* location) const
+void Editor::getSite(Site* site) const
 {
-  location->document(m_document);
-  location->sprite(m_sprite);
-  location->layer(m_layer);
-  location->frame(m_frame);
+  site->document(m_document);
+  site->sprite(m_sprite);
+  site->layer(m_layer);
+  site->frame(m_frame);
 }
 
-DocumentLocation Editor::getDocumentLocation() const
+Site Editor::getSite() const
 {
-  DocumentLocation location;
-  getDocumentLocation(&location);
-  return location;
+  Site site;
+  getSite(&site);
+  return site;
 }
 
 void Editor::setDefaultScroll()
@@ -745,10 +744,10 @@ void Editor::flashCurrentLayer()
   if (!App::instance()->preferences().experimental.flashLayer())
     return;
 
-  DocumentLocation loc = getDocumentLocation();
+  Site site = getSite();
 
   int x, y;
-  const Image* src_image = loc.image(&x, &y);
+  const Image* src_image = site.image(&x, &y);
   if (src_image) {
     m_renderEngine.removePreviewImage();
 
@@ -1484,8 +1483,7 @@ void Editor::pasteImage(const Image* image, const gfx::Point& pos)
 
   PixelsMovementPtr pixelsMovement(
     new PixelsMovement(UIContext::instance(),
-      getDocumentLocation(),
-      image, gfx::Point(x, y), opacity, "Paste"));
+      getSite(), image, gfx::Point(x, y), opacity, "Paste"));
 
   // Select the pasted image so the user can move it and transform it.
   pixelsMovement->maskImage(image);
diff --git a/src/app/ui/editor/editor.h b/src/app/ui/editor/editor.h
index e0530409d..52eabed7e 100644
--- a/src/app/ui/editor/editor.h
+++ b/src/app/ui/editor/editor.h
@@ -28,8 +28,9 @@
 #include "ui/widget.h"
 
 namespace doc {
-  class Sprite;
   class Layer;
+  class Site;
+  class Sprite;
 }
 namespace gfx {
   class Region;
@@ -41,7 +42,6 @@ namespace ui {
 
 namespace app {
   class Context;
-  class DocumentLocation;
   class DocumentView;
   class EditorCustomizationDelegate;
   class PixelsMovement;
@@ -106,8 +106,8 @@ namespace app {
     Layer* layer() { return m_layer; }
     frame_t frame() { return m_frame; }
 
-    void getDocumentLocation(DocumentLocation* location) const;
-    DocumentLocation getDocumentLocation() const;
+    void getSite(Site* site) const;
+    Site getSite() const;
 
     void setLayer(const Layer* layer);
     void setFrame(frame_t frame);
diff --git a/src/app/ui/editor/pixels_movement.cpp b/src/app/ui/editor/pixels_movement.cpp
index 801e37f9f..f55b7a4a4 100644
--- a/src/app/ui/editor/pixels_movement.cpp
+++ b/src/app/ui/editor/pixels_movement.cpp
@@ -32,6 +32,7 @@
 #include "doc/cel.h"
 #include "doc/image.h"
 #include "doc/mask.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 #include "gfx/region.h"
 #include "render/render.h"
@@ -44,14 +45,14 @@ static inline const base::Vector2d<double> point2Vector(const gfx::PointT<T>& pt
 }
 
 PixelsMovement::PixelsMovement(Context* context,
-  DocumentLocation location,
+  Site site,
   const Image* moveThis, const gfx::Point& initialPos, int opacity,
   const char* operationName)
   : m_reader(context)
-  , m_location(location)
-  , m_document(location.document())
-  , m_sprite(location.sprite())
-  , m_layer(location.layer())
+  , m_site(site)
+  , m_document(static_cast<app::Document*>(site.document()))
+  , m_sprite(site.sprite())
+  , m_layer(site.layer())
   , m_transaction(context, operationName)
   , m_setMaskCmd(nullptr)
   , m_isDragging(false)
@@ -443,7 +444,7 @@ void PixelsMovement::stampImage()
     {
       // Expand the canvas to paste the image in the fully visible
       // portion of sprite.
-      ExpandCelCanvas expand(m_location,
+      ExpandCelCanvas expand(m_site,
         TiledMode::NONE, m_transaction,
         ExpandCelCanvas::None);
 
@@ -473,7 +474,7 @@ void PixelsMovement::dropImageTemporarily()
 
     // TODO Add undo information so the user can undo each transformation step.
 
-    // Displace the pivot to the new location:
+    // Displace the pivot to the new site:
     if (m_adjustPivot) {
       m_adjustPivot = false;
 
diff --git a/src/app/ui/editor/pixels_movement.h b/src/app/ui/editor/pixels_movement.h
index 4953d4683..401d90c7e 100644
--- a/src/app/ui/editor/pixels_movement.h
+++ b/src/app/ui/editor/pixels_movement.h
@@ -11,11 +11,12 @@
 
 #include "app/context_access.h"
 #include "app/settings/settings_observers.h"
-#include "app/ui/editor/handle_type.h"
 #include "app/transaction.h"
+#include "app/ui/editor/handle_type.h"
 #include "base/shared_ptr.h"
-#include "gfx/size.h"
 #include "doc/algorithm/flip_type.h"
+#include "doc/site.h"
+#include "gfx/size.h"
 
 namespace doc {
   class Image;
@@ -47,7 +48,7 @@ namespace app {
     // The "moveThis" image specifies the chunk of pixels to be moved.
     // The "x" and "y" parameters specify the initial position of the image.
     PixelsMovement(Context* context,
-      DocumentLocation location,
+      Site site,
       const Image* moveThis,
       const gfx::Point& initialPos, int opacity,
       const char* operationName);
@@ -104,7 +105,7 @@ namespace app {
     void updateDocumentMask();
 
     const ContextReader m_reader;
-    DocumentLocation m_location;
+    Site m_site;
     Document* m_document;
     Sprite* m_sprite;
     Layer* m_layer;
diff --git a/src/app/ui/editor/standby_state.cpp b/src/app/ui/editor/standby_state.cpp
index a3ef4d1f4..17c28fcd1 100644
--- a/src/app/ui/editor/standby_state.cpp
+++ b/src/app/ui/editor/standby_state.cpp
@@ -15,7 +15,6 @@
 #include "app/color_picker.h"
 #include "app/commands/commands.h"
 #include "app/commands/params.h"
-#include "app/document_location.h"
 #include "app/ini_file.h"
 #include "app/settings/settings.h"
 #include "app/tools/ink.h"
@@ -145,10 +144,10 @@ bool StandbyState::onMouseDown(Editor* editor, MouseMessage* msg)
 
   UIContext* context = UIContext::instance();
   tools::Ink* clickedInk = editor->getCurrentEditorInk();
-  DocumentLocation location;
-  editor->getDocumentLocation(&location);
-  Document* document = location.document();
-  Layer* layer = location.layer();
+  Site site;
+  editor->getSite(&site);
+  app::Document* document = static_cast<app::Document*>(site.document());
+  Layer* layer = site.layer();
 
   // When an editor is clicked the current view is changed.
   context->setActiveView(editor->getDocumentView());
@@ -164,7 +163,7 @@ bool StandbyState::onMouseDown(Editor* editor, MouseMessage* msg)
       gfx::Point cursor = editor->screenToEditor(msg->position());
 
       ColorPicker picker;
-      picker.pickColor(location, cursor, ColorPicker::FromComposition);
+      picker.pickColor(site, cursor, ColorPicker::FromComposition);
 
       if (layer != picker.layer()) {
         layer = picker.layer();
@@ -217,7 +216,7 @@ bool StandbyState::onMouseDown(Editor* editor, MouseMessage* msg)
 
       if (handle != NoHandle) {
         int x, y, opacity;
-        Image* image = location.image(&x, &y, &opacity);
+        Image* image = site.image(&x, &y, &opacity);
         if (layer && image) {
           if (!layer->isEditable()) {
             StatusBar::instance()->showTip(1000,
@@ -370,7 +369,7 @@ bool StandbyState::onUpdateStatusBar(Editor* editor)
   else if (ink->isEyedropper()) {
     bool grabAlpha = UIContext::instance()->settings()->getGrabAlpha();
     ColorPicker picker;
-    picker.pickColor(editor->getDocumentLocation(),
+    picker.pickColor(editor->getSite(),
       spritePos,
       grabAlpha ?
       ColorPicker::FromActiveLayer:
@@ -416,12 +415,12 @@ void StandbyState::transformSelection(Editor* editor, MouseMessage* msg, HandleT
   try {
     EditorCustomizationDelegate* customization = editor->getCustomizationDelegate();
     Document* document = editor->document();
-    base::UniquePtr<Image> tmpImage(new_image_from_mask(editor->getDocumentLocation()));
+    base::UniquePtr<Image> tmpImage(new_image_from_mask(editor->getSite()));
     gfx::Point origin = document->mask()->bounds().getOrigin();
     int opacity = 255;
     PixelsMovementPtr pixelsMovement(
       new PixelsMovement(UIContext::instance(),
-        editor->getDocumentLocation(),
+        editor->getSite(),
         tmpImage, origin, opacity,
         "Transformation"));
 
diff --git a/src/app/ui/editor/tool_loop_impl.cpp b/src/app/ui/editor/tool_loop_impl.cpp
index 942b7a835..dc064a84f 100644
--- a/src/app/ui/editor/tool_loop_impl.cpp
+++ b/src/app/ui/editor/tool_loop_impl.cpp
@@ -112,7 +112,7 @@ public:
                       getInk()->isSlice() ||
                       getInk()->isZoom()) ? DoesntModifyDocument:
                                             ModifyDocument))
-    , m_expandCelCanvas(editor->getDocumentLocation(),
+    , m_expandCelCanvas(editor->getSite(),
         m_docPref.tiled.mode(),
         m_transaction,
         ExpandCelCanvas::Flags(
diff --git a/src/app/ui/keyboard_shortcuts.cpp b/src/app/ui/keyboard_shortcuts.cpp
index 1ecd93cea..e1c17789f 100644
--- a/src/app/ui/keyboard_shortcuts.cpp
+++ b/src/app/ui/keyboard_shortcuts.cpp
@@ -17,7 +17,6 @@
 #include "app/commands/commands.h"
 #include "app/commands/params.h"
 #include "app/document.h"
-#include "app/document_location.h"
 #include "app/settings/settings.h"
 #include "app/tools/ink.h"
 #include "app/tools/tool.h"
@@ -635,8 +634,7 @@ void KeyboardShortcuts::disableAccel(const ui::Accelerator& accel, KeyContext ke
 KeyContext KeyboardShortcuts::getCurrentKeyContext()
 {
   app::Context* ctx = UIContext::instance();
-  DocumentLocation location = ctx->activeLocation();
-  Document* doc = location.document();
+  Document* doc = ctx->activeDocument();
 
   if (doc &&
       doc->isMaskVisible() &&
diff --git a/src/app/ui/timeline.cpp b/src/app/ui/timeline.cpp
index 71b9a08d6..0645c4910 100644
--- a/src/app/ui/timeline.cpp
+++ b/src/app/ui/timeline.cpp
@@ -157,24 +157,24 @@ void Timeline::updateUsingEditor(Editor* editor)
   else
     return;                // No editor specified.
 
-  DocumentLocation location;
+  Site site;
   DocumentView* view = m_editor->getDocumentView();
-  view->getDocumentLocation(&location);
+  view->getSite(&site);
 
-  location.document()->addObserver(this);
+  site.document()->addObserver(this);
 
   // If we are already in the same position as the "editor", we don't
   // need to update the at all timeline.
-  if (m_document == location.document() &&
-      m_sprite == location.sprite() &&
-      m_layer == location.layer() &&
-      m_frame == location.frame())
+  if (m_document == site.document() &&
+      m_sprite == site.sprite() &&
+      m_layer == site.layer() &&
+      m_frame == site.frame())
     return;
 
-  m_document = location.document();
-  m_sprite = location.sprite();
-  m_layer = location.layer();
-  m_frame = location.frame();
+  m_document = static_cast<app::Document*>(site.document());
+  m_sprite = site.sprite();
+  m_layer = site.layer();
+  m_frame = site.frame();
   m_state = STATE_STANDBY;
   m_hot.part = PART_NOTHING;
   m_clk.part = PART_NOTHING;
diff --git a/src/app/ui_context.cpp b/src/app/ui_context.cpp
index bc68cbee8..b8c41c754 100644
--- a/src/app/ui_context.cpp
+++ b/src/app/ui_context.cpp
@@ -11,7 +11,6 @@
 
 #include "app/app.h"
 #include "app/document.h"
-#include "app/document_location.h"
 #include "app/modules/editors.h"
 #include "app/pref/preferences.h"
 #include "app/settings/ui_settings_impl.h"
@@ -26,15 +25,17 @@
 #include "app/ui/workspace_tabs.h"
 #include "app/ui_context.h"
 #include "base/mutex.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 
 namespace app {
 
-UIContext* UIContext::m_instance = NULL;
+UIContext* UIContext::m_instance = nullptr;
 
 UIContext::UIContext()
   : Context(new UISettingsImpl)
-  , m_lastSelectedView(NULL)
+  , m_lastSelectedDoc(nullptr)
+  , m_lastSelectedView(nullptr)
 {
   documents().addObserver(&App::instance()->preferences());
 
@@ -81,8 +82,6 @@ void UIContext::setActiveView(DocumentView* docView)
       (docView && docView->isPreview()))
     return;
 
-  setActiveDocument(docView ? docView->getDocument(): NULL);
-
   MainWindow* mainWin = App::instance()->getMainWindow();
   if (docView) {
     mainWin->getTabsBar()->selectTab(docView);
@@ -112,6 +111,16 @@ void UIContext::setActiveView(DocumentView* docView)
   m_lastSelectedView = docView;
 }
 
+void UIContext::setActiveDocument(Document* document)
+{
+  m_lastSelectedDoc = document;
+
+  DocumentView* docView = getFirstDocumentView(document);
+  ASSERT(docView);
+  if (docView)
+    setActiveView(docView);
+}
+
 DocumentView* UIContext::getFirstDocumentView(Document* document) const
 {
   Workspace* workspace = App::instance()->getMainWindow()->getWorkspace();
@@ -138,14 +147,14 @@ Editor* UIContext::activeEditor()
 
 void UIContext::onAddDocument(doc::Document* doc)
 {
-  Context::onAddDocument(doc);
+  m_lastSelectedDoc = static_cast<app::Document*>(doc);
 
   // We don't create views in batch mode.
   if (!App::instance()->isGui())
     return;
 
   // Add a new view for this document
-  DocumentView* view = new DocumentView(static_cast<app::Document*>(doc), DocumentView::Normal);
+  DocumentView* view = new DocumentView(m_lastSelectedDoc, DocumentView::Normal);
 
   // Add a tab with the new view for the document
   App::instance()->getMainWindow()->getWorkspace()->addView(view);
@@ -156,6 +165,9 @@ void UIContext::onAddDocument(doc::Document* doc)
 
 void UIContext::onRemoveDocument(doc::Document* doc)
 {
+  if (doc == m_lastSelectedDoc)
+    m_lastSelectedDoc = nullptr;
+
   // We don't destroy views in batch mode.
   if (isUiAvailable()) {
     Workspace* workspace = App::instance()->getMainWindow()->getWorkspace();
@@ -175,22 +187,20 @@ void UIContext::onRemoveDocument(doc::Document* doc)
       delete docView;
     }
   }
-
-  Context::onRemoveDocument(doc);
 }
 
-void UIContext::onGetActiveLocation(DocumentLocation* location) const
+void UIContext::onGetActiveSite(Site* site) const
 {
   DocumentView* view = activeView();
   if (view) {
-    view->getDocumentLocation(location);
+    view->getSite(site);
   }
-  // Default/dummy location (maybe for batch/command line mode)
-  else if (Document* doc = activeDocument()) {
-    location->document(doc);
-    location->sprite(doc->sprite());
-    location->layer(doc->sprite()->indexToLayer(LayerIndex(0)));
-    location->frame(0);
+  // Default/dummy site (maybe for batch/command line mode)
+  else if (Document* doc = m_lastSelectedDoc) {
+    site->document(doc);
+    site->sprite(doc->sprite());
+    site->layer(doc->sprite()->indexToLayer(LayerIndex(0)));
+    site->frame(0);
   }
 }
 
diff --git a/src/app/ui_context.h b/src/app/ui_context.h
index dbd7aed52..327e2173e 100644
--- a/src/app/ui_context.h
+++ b/src/app/ui_context.h
@@ -29,6 +29,7 @@ namespace app {
 
     DocumentView* activeView() const;
     void setActiveView(DocumentView* documentView);
+    void setActiveDocument(Document* document);
 
     DocumentView* getFirstDocumentView(Document* document) const;
 
@@ -40,11 +41,12 @@ namespace app {
     Editor* getEditorFor(Document* document);
 
   protected:
-    virtual void onAddDocument(doc::Document* doc) override;
-    virtual void onRemoveDocument(doc::Document* doc) override;
-    virtual void onGetActiveLocation(DocumentLocation* location) const override;
+    void onAddDocument(doc::Document* doc) override;
+    void onRemoveDocument(doc::Document* doc) override;
+    void onGetActiveSite(doc::Site* site) const override;
 
   private:
+    Document* m_lastSelectedDoc;
     DocumentView* m_lastSelectedView;
     static UIContext* m_instance;
   };
diff --git a/src/app/util/clipboard.cpp b/src/app/util/clipboard.cpp
index 07f32369b..a0c448f41 100644
--- a/src/app/util/clipboard.cpp
+++ b/src/app/util/clipboard.cpp
@@ -16,7 +16,6 @@
 #include "app/context_access.h"
 #include "app/document.h"
 #include "app/document_api.h"
-#include "app/document_location.h"
 #include "app/document_range.h"
 #include "app/modules/editors.h"
 #include "app/modules/gfx.h"
@@ -83,7 +82,7 @@ namespace {
 using namespace doc;
 
 static void set_clipboard_image(Image* image, Palette* palette, bool set_system_clipboard);
-static bool copy_from_document(const DocumentLocation& location);
+static bool copy_from_document(const Site& site);
 
 static bool first_time = true;
 
@@ -120,20 +119,20 @@ static void set_clipboard_image(Image* image, Palette* palette, bool set_system_
   clipboard_range.invalidate();
 }
 
-static bool copy_from_document(const DocumentLocation& location)
+static bool copy_from_document(const Site& site)
 {
-  const Document* document = location.document();
+  const app::Document* document = static_cast<const app::Document*>(site.document());
 
   ASSERT(document != NULL);
   ASSERT(document->isMaskVisible());
 
-  Image* image = new_image_from_mask(location);
+  Image* image = new_image_from_mask(site);
   if (!image)
     return false;
 
   clipboard_pos = document->mask()->bounds().getOrigin();
 
-  const Palette* pal = document->sprite()->palette(location.frame());
+  const Palette* pal = document->sprite()->palette(site.frame());
   set_clipboard_image(image, pal ? new Palette(*pal): NULL, true);
   return true;
 }
@@ -175,7 +174,7 @@ void clipboard::cut(ContextWriter& writer)
   ASSERT(writer.sprite() != NULL);
   ASSERT(writer.layer() != NULL);
 
-  if (!copy_from_document(*writer.location())) {
+  if (!copy_from_document(*writer.site())) {
     Console console;
     console.printf("Can't copying an image portion from the current layer\n");
   }
@@ -195,7 +194,7 @@ void clipboard::copy(const ContextReader& reader)
 {
   ASSERT(reader.document() != NULL);
 
-  if (!copy_from_document(*reader.location())) {
+  if (!copy_from_document(*reader.site())) {
     Console console;
     console.printf("Can't copying an image portion from the current layer\n");
     return;
diff --git a/src/app/util/expand_cel_canvas.cpp b/src/app/util/expand_cel_canvas.cpp
index 10dd87d6b..b7b7d1edc 100644
--- a/src/app/util/expand_cel_canvas.cpp
+++ b/src/app/util/expand_cel_canvas.cpp
@@ -18,7 +18,6 @@
 #include "app/cmd/set_cel_position.h"
 #include "app/context.h"
 #include "app/document.h"
-#include "app/document_location.h"
 #include "app/transaction.h"
 #include "app/util/range_utils.h"
 #include "base/unique_ptr.h"
@@ -26,6 +25,7 @@
 #include "doc/image.h"
 #include "doc/layer.h"
 #include "doc/primitives.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 
 namespace {
@@ -53,11 +53,11 @@ static void create_buffers()
 
 namespace app {
 
-ExpandCelCanvas::ExpandCelCanvas(DocumentLocation location,
+ExpandCelCanvas::ExpandCelCanvas(Site site,
   TiledMode tiledMode, Transaction& transaction, Flags flags)
-  : m_document(location.document())
-  , m_sprite(location.sprite())
-  , m_layer(location.layer())
+  : m_document(static_cast<app::Document*>(site.document()))
+  , m_sprite(site.sprite())
+  , m_layer(site.layer())
   , m_cel(NULL)
   , m_celImage(NULL)
   , m_celCreated(false)
@@ -71,7 +71,7 @@ ExpandCelCanvas::ExpandCelCanvas(DocumentLocation location,
   create_buffers();
 
   if (m_layer->isImage()) {
-    m_cel = m_layer->cel(location.frame());
+    m_cel = m_layer->cel(site.frame());
     if (m_cel)
       m_celImage = m_cel->imageRef();
   }
@@ -79,7 +79,7 @@ ExpandCelCanvas::ExpandCelCanvas(DocumentLocation location,
   // Create a new cel
   if (m_cel == NULL) {
     m_celCreated = true;
-    m_cel = new Cel(location.frame(), ImageRef(NULL));
+    m_cel = new Cel(site.frame(), ImageRef(NULL));
   }
 
   m_origCelPos = m_cel->position();
diff --git a/src/app/util/expand_cel_canvas.h b/src/app/util/expand_cel_canvas.h
index a6b27dafc..f2339a39b 100644
--- a/src/app/util/expand_cel_canvas.h
+++ b/src/app/util/expand_cel_canvas.h
@@ -20,12 +20,12 @@ namespace doc {
   class Cel;
   class Image;
   class Layer;
+  class Site;
   class Sprite;
 }
 
 namespace app {
   class Document;
-  class DocumentLocation;
   class Transaction;
 
   using namespace filters;
@@ -45,7 +45,7 @@ namespace app {
       UseModifiedRegionAsUndoInfo = 2,
     };
 
-    ExpandCelCanvas(DocumentLocation location,
+    ExpandCelCanvas(Site site,
       TiledMode tiledMode, Transaction& undo, Flags flags);
     ~ExpandCelCanvas();
 
diff --git a/src/app/util/new_image_from_mask.cpp b/src/app/util/new_image_from_mask.cpp
index 8bfd79e3e..78a0e66db 100644
--- a/src/app/util/new_image_from_mask.cpp
+++ b/src/app/util/new_image_from_mask.cpp
@@ -12,25 +12,25 @@
 #include "app/util/new_image_from_mask.h"
 
 #include "app/document.h"
-#include "app/document_location.h"
 #include "doc/image.h"
 #include "doc/image_bits.h"
 #include "doc/image_traits.h"
 #include "doc/mask.h"
+#include "doc/site.h"
 
 namespace app {
 
 using namespace doc;
 
-Image* new_image_from_mask(const DocumentLocation& location)
+Image* new_image_from_mask(const Site& site)
 {
-  const Sprite* srcSprite = location.sprite();
-  const Mask* srcMask = location.document()->mask();
+  const Sprite* srcSprite = site.sprite();
+  const Mask* srcMask = static_cast<const app::Document*>(site.document())->mask();
   const Image* srcMaskBitmap = srcMask->bitmap();
   const gfx::Rect& srcBounds = srcMask->bounds();
   int x, y, u, v, getx, gety;
   Image *dst;
-  const Image *src = location.image(&x, &y);
+  const Image *src = site.image(&x, &y);
 
   ASSERT(srcSprite);
   ASSERT(srcMask);
diff --git a/src/app/util/new_image_from_mask.h b/src/app/util/new_image_from_mask.h
index a768b1c1e..035a7c6dd 100644
--- a/src/app/util/new_image_from_mask.h
+++ b/src/app/util/new_image_from_mask.h
@@ -11,12 +11,12 @@
 
 namespace doc {
   class Image;
+  class Site;
 }
 
 namespace app {
-  class DocumentLocation;
 
-  doc::Image* new_image_from_mask(const DocumentLocation& location);
+  doc::Image* new_image_from_mask(const doc::Site& site);
 
 } // namespace app
 
diff --git a/src/doc/CMakeLists.txt b/src/doc/CMakeLists.txt
index 5e23365f4..502825b1c 100644
--- a/src/doc/CMakeLists.txt
+++ b/src/doc/CMakeLists.txt
@@ -42,6 +42,7 @@ add_library(doc-lib
   primitives.cpp
   remap.cpp
   rgbmap.cpp
+  site.cpp
   sprite.cpp
   sprites.cpp
   string_io.cpp
diff --git a/src/doc/context.cpp b/src/doc/context.cpp
index 9bb70ab50..b4c5e1545 100644
--- a/src/doc/context.cpp
+++ b/src/doc/context.cpp
@@ -10,7 +10,7 @@
 
 #include "doc/context.h"
 
-#include <algorithm>
+#include "doc/site.h"
 
 namespace doc {
 
@@ -23,30 +23,46 @@ Context::Context()
 
 Context::~Context()
 {
-  setActiveDocument(NULL);
   m_docs.removeObserver(this);
 }
 
+Site Context::activeSite() const
+{
+  Site site;
+  onGetActiveSite(&site);
+  return site;
+}
+
 Document* Context::activeDocument() const
 {
-  return m_activeDoc;
+  Site site;
+  onGetActiveSite(&site);
+  return site.document();
 }
 
-void Context::setActiveDocument(Document* doc)
+void Context::notifyActiveDocumentChanged(Document* doc)
 {
-  m_activeDoc = doc;
-  notifyObservers(&ContextObserver::onSetActiveDocument, doc);
+  notifyObservers(&ContextObserver::onActiveDocumentChange, doc);
+}
+
+void Context::notifyActiveSiteChanged(Site* site)
+{
+  notifyObservers(&ContextObserver::onActiveSiteChange, site);
+}
+
+void Context::onGetActiveSite(Site* site) const
+{
+  ASSERT(false);
 }
 
 void Context::onAddDocument(Document* doc)
 {
-  m_activeDoc = doc;
+  // Do nothing
 }
 
 void Context::onRemoveDocument(Document* doc)
 {
-  if (m_activeDoc == doc)
-    setActiveDocument(!m_docs.empty() ? m_docs.back() : NULL);
+  // Do nothing
 }
 
 } // namespace doc
diff --git a/src/doc/context.h b/src/doc/context.h
index 4c2928966..a0fdbe989 100644
--- a/src/doc/context.h
+++ b/src/doc/context.h
@@ -28,10 +28,14 @@ namespace doc {
     const Documents& documents() const { return m_docs; }
     Documents& documents() { return m_docs; }
 
+    Site activeSite() const;
     Document* activeDocument() const;
-    void setActiveDocument(Document* doc);
 
-    // DocumentsObserver impl
+  protected:
+    void notifyActiveDocumentChanged(Document* doc);
+    void notifyActiveSiteChanged(Site* site);
+
+    virtual void onGetActiveSite(Site* site) const;
     virtual void onAddDocument(Document* doc) override;
     virtual void onRemoveDocument(Document* doc) override;
 
diff --git a/src/doc/context_observer.h b/src/doc/context_observer.h
index 2715c9196..bdfa54271 100644
--- a/src/doc/context_observer.h
+++ b/src/doc/context_observer.h
@@ -1,5 +1,5 @@
 // Aseprite Document Library
-// Copyright (c) 2001-2014 David Capello
+// Copyright (c) 2001-2015 David Capello
 //
 // This file is released under the terms of the MIT license.
 // Read LICENSE.txt for more information.
@@ -11,11 +11,13 @@
 namespace doc {
 
   class Document;
+  class Site;
 
   class ContextObserver {
   public:
     virtual ~ContextObserver() { }
-    virtual void onSetActiveDocument(Document* document) { }
+    virtual void onActiveDocumentChange(Document* document) { }
+    virtual void onActiveSiteChange(Site* site) { }
   };
 
 } // namespace doc
diff --git a/src/doc/doc.h b/src/doc/doc.h
index c80eea296..7d7e94974 100644
--- a/src/doc/doc.h
+++ b/src/doc/doc.h
@@ -28,6 +28,7 @@
 #include "doc/primitives_fast.h"
 #include "doc/remap.h"
 #include "doc/rgbmap.h"
+#include "doc/site.h"
 #include "doc/sprite.h"
 
 #endif
diff --git a/src/app/document_location.cpp b/src/doc/site.cpp
similarity index 56%
rename from src/app/document_location.cpp
rename to src/doc/site.cpp
index 7be5cb468..ee69d24d4 100644
--- a/src/app/document_location.cpp
+++ b/src/doc/site.cpp
@@ -1,42 +1,39 @@
-// Aseprite
-// Copyright (C) 2001-2015  David Capello
+// Aseprite Document Library
+// Copyright (c) 2001-2015 David Capello
 //
-// This program is free software; you can redistribute it and/or modify
-// it under the terms of the GNU General Public License version 2 as
-// published by the Free Software Foundation.
+// This file is released under the terms of the MIT license.
+// Read LICENSE.txt for more information.
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
-#include "app/document_location.h"
+#include "doc/site.h"
 
 #include "doc/cel.h"
 #include "doc/layer.h"
 #include "doc/sprite.h"
 
-namespace app {
+namespace doc {
 
-using namespace doc;
-
-LayerIndex DocumentLocation::layerIndex() const
+LayerIndex Site::layerIndex() const
 {
   return (m_sprite && m_layer ?
           m_sprite->layerToIndex(m_layer): LayerIndex());
 }
 
-void DocumentLocation::layerIndex(LayerIndex layerIndex)
+void Site::layerIndex(LayerIndex layerIndex)
 {
   ASSERT(m_sprite != NULL);
   m_layer = m_sprite->indexToLayer(layerIndex);
 }
 
-Palette* DocumentLocation::palette()
+Palette* Site::palette()
 {
   return (m_sprite ? m_sprite->palette(m_frame): NULL);
 }
 
-const Cel* DocumentLocation::cel() const
+const Cel* Site::cel() const
 {
   if (m_layer)
     return m_layer->cel(m_frame);
@@ -44,7 +41,7 @@ const Cel* DocumentLocation::cel() const
     return NULL;
 }
 
-Cel* DocumentLocation::cel()
+Cel* Site::cel()
 {
   if (m_layer)
     return m_layer->cel(m_frame);
@@ -52,7 +49,7 @@ Cel* DocumentLocation::cel()
     return NULL;
 }
 
-Image* DocumentLocation::image(int* x, int* y, int* opacity) const
+Image* Site::image(int* x, int* y, int* opacity) const
 {
   Image* image = NULL;
 
@@ -68,9 +65,9 @@ Image* DocumentLocation::image(int* x, int* y, int* opacity) const
   return image;
 }
 
-Palette* DocumentLocation::palette() const
+Palette* Site::palette() const
 {
   return (m_sprite ? m_sprite->palette(m_frame): NULL);
 }
 
-} // namespace app
+} // namespace doc
diff --git a/src/app/document_location.h b/src/doc/site.h
similarity index 67%
rename from src/app/document_location.h
rename to src/doc/site.h
index 851affded..e459befac 100644
--- a/src/app/document_location.h
+++ b/src/doc/site.h
@@ -1,36 +1,31 @@
-// Aseprite
-// Copyright (C) 2001-2015  David Capello
+// Aseprite Document Library
+// Copyright (c) 2001-2015 David Capello
 //
-// This program is free software; you can redistribute it and/or modify
-// it under the terms of the GNU General Public License version 2 as
-// published by the Free Software Foundation.
+// This file is released under the terms of the MIT license.
+// Read LICENSE.txt for more information.
 
-#ifndef APP_DOCUMENT_LOCATION_H_INCLUDED
-#define APP_DOCUMENT_LOCATION_H_INCLUDED
+#ifndef DOC_SITE_H_INCLUDED
+#define DOC_SITE_H_INCLUDED
 #pragma once
 
 #include "doc/frame.h"
 #include "doc/layer_index.h"
 
 namespace doc {
+
   class Cel;
+  class Document;
   class Image;
   class Layer;
   class Palette;
   class Sprite;
-}
 
-namespace app {
-  class Document;
-
-  using namespace doc;
-
-  // Specifies the current location in a context. If we are in the
-  // UIContext, it means the location in the current Editor (current
-  // document, sprite, layer, frame, etc.).
-  class DocumentLocation {
+  // Specifies the current location in a context. E.g. the location in
+  // the current Editor (current document, sprite, layer, frame,
+  // etc.).
+  class Site {
   public:
-    DocumentLocation()
+    Site()
       : m_document(NULL)
       , m_sprite(NULL)
       , m_layer(NULL)
diff --git a/src/doc/test_context.h b/src/doc/test_context.h
new file mode 100644
index 000000000..a51aed278
--- /dev/null
+++ b/src/doc/test_context.h
@@ -0,0 +1,55 @@
+// Aseprite Document Library
+// Copyright (c) 2001-2015 David Capello
+//
+// This file is released under the terms of the MIT license.
+// Read LICENSE.txt for more information.
+
+#ifndef DOC_TEST_CONTEXT_H_INCLUDED
+#define DOC_TEST_CONTEXT_H_INCLUDED
+#pragma once
+
+#include "doc/context.h"
+#include "doc/document.h"
+#include "doc/layer.h"
+#include "doc/site.h"
+#include "doc/sprite.h"
+
+namespace doc {
+
+  template<typename Base>
+  class TestContextT : public Base {
+  public:
+    TestContextT() : m_activeDoc(nullptr) {
+    }
+
+  protected:
+
+    void onGetActiveSite(Site* site) const override {
+      Document* doc = m_activeDoc;
+      if (!doc)
+        return;
+
+      site->document(doc);
+      site->sprite(doc->sprite());
+      site->layer(doc->sprite()->folder()->getFirstLayer());
+      site->frame(0);
+    }
+
+    void onAddDocument(Document* doc) override {
+      notifyActiveDocumentChanged(m_activeDoc = doc);
+    }
+
+    void onRemoveDocument(Document* doc) override {
+      if (m_activeDoc == doc)
+        notifyActiveDocumentChanged(m_activeDoc = nullptr);
+    }
+
+  private:
+    Document* m_activeDoc;
+  };
+
+  typedef TestContextT<Context> TestContext;
+
+} // namespace doc
+
+#endif