diff --git a/MapControl/MapControl.csproj b/MapControl/MapControl.csproj
index dce34dd9..4c666b88 100644
--- a/MapControl/MapControl.csproj
+++ b/MapControl/MapControl.csproj
@@ -68,6 +68,7 @@
     <Compile Include="TileLayer.cs" />
     <Compile Include="TileLayerCollection.cs" />
     <Compile Include="TileSource.cs" />
+    <Compile Include="ViewportPosition.cs" />
   </ItemGroup>
   <ItemGroup>
     <Page Include="Themes\Generic.xaml">
diff --git a/MapControl/MapItemsControl.cs b/MapControl/MapItemsControl.cs
index 477111d0..6ef620ec 100644
--- a/MapControl/MapItemsControl.cs
+++ b/MapControl/MapItemsControl.cs
@@ -121,8 +121,9 @@ namespace MapControl
                     foreach (object item in Items)
                     {
                         MapItem mapItem = GetMapItem(item);
+                        ViewportPosition viewportPosition = MapPanel.GetViewportPosition(mapItem);
 
-                        if (mapItem != null && MapPanel.HasViewportPosition(mapItem) && geometry.FillContains(MapPanel.GetViewportPosition(mapItem)))
+                        if (mapItem != null && viewportPosition != null && geometry.FillContains(viewportPosition.Position))
                         {
                             SelectedItems.Add(item);
                         }
diff --git a/MapControl/MapPanel.cs b/MapControl/MapPanel.cs
index 8ccda801..c84cd822 100644
--- a/MapControl/MapPanel.cs
+++ b/MapControl/MapPanel.cs
@@ -2,9 +2,9 @@
 // Copyright © 2012 Clemens Fischer
 // Licensed under the Microsoft Public License (Ms-PL)
 
-using System;
 using System.Windows;
 using System.Windows.Controls;
+using System.Windows.Media;
 
 namespace MapControl
 {
@@ -12,8 +12,7 @@ namespace MapControl
     /// Positions child elements on a Map. A child element's position is specified by the
     /// attached property Location, given as geographic location with latitude and longitude.
     /// The attached property ViewportPosition gets a child element's position in viewport
-    /// coordinates. IsInsideMapBounds indicates if the viewport coordinates are located
-    /// inside the visible part of the map.
+    /// coordinates and indicates if the coordinates are located inside the bounds of the ParentMap.
     /// </summary>
     public class MapPanel : Panel
     {
@@ -23,16 +22,13 @@ namespace MapControl
 
         public static readonly DependencyProperty LocationProperty = DependencyProperty.RegisterAttached(
             "Location", typeof(Location), typeof(MapPanel),
-            new FrameworkPropertyMetadata(null, FrameworkPropertyMetadataOptions.AffectsRender, LocationPropertyChanged));
+            new FrameworkPropertyMetadata(LocationPropertyChanged));
 
         private static readonly DependencyPropertyKey ViewportPositionPropertyKey = DependencyProperty.RegisterAttachedReadOnly(
-            "ViewportPosition", typeof(Point), typeof(MapPanel), null);
-
-        private static readonly DependencyPropertyKey IsInsideMapBoundsPropertyKey = DependencyProperty.RegisterAttachedReadOnly(
-            "IsInsideMapBounds", typeof(bool), typeof(MapPanel), null);
+            "ViewportPosition", typeof(ViewportPosition), typeof(MapPanel),
+            new FrameworkPropertyMetadata(ViewportPositionPropertyChanged));
 
         public static readonly DependencyProperty ViewportPositionProperty = ViewportPositionPropertyKey.DependencyProperty;
-        public static readonly DependencyProperty IsInsideMapBoundsProperty = IsInsideMapBoundsPropertyKey.DependencyProperty;
 
         public MapPanel()
         {
@@ -59,19 +55,9 @@ namespace MapControl
             element.SetValue(LocationProperty, value);
         }
 
-        public static bool HasViewportPosition(UIElement element)
+        public static ViewportPosition GetViewportPosition(UIElement element)
         {
-            return element.ReadLocalValue(ViewportPositionProperty) != DependencyProperty.UnsetValue;
-        }
-
-        public static Point GetViewportPosition(UIElement element)
-        {
-            return (Point)element.GetValue(ViewportPositionProperty);
-        }
-
-        public static bool GetIsInsideMapBounds(UIElement element)
-        {
-            return (bool)element.GetValue(IsInsideMapBoundsProperty);
+            return (ViewportPosition)element.GetValue(ViewportPositionProperty);
         }
 
         protected override Size MeasureOverride(Size availableSize)
@@ -90,10 +76,9 @@ namespace MapControl
         {
             foreach (UIElement element in InternalChildren)
             {
-                object viewportPosition = element.ReadLocalValue(ViewportPositionProperty);
+                ViewportPosition viewportPosition = GetViewportPosition(element);
 
-                if (viewportPosition == DependencyProperty.UnsetValue ||
-                    !ArrangeElement(element, (Point)viewportPosition))
+                if (viewportPosition == null || !ArrangeElement(element, viewportPosition))
                 {
                     ArrangeElement(element, finalSize);
                 }
@@ -102,6 +87,11 @@ namespace MapControl
             return finalSize;
         }
 
+        protected virtual Point GetArrangePosition(ViewportPosition viewportPosition)
+        {
+            return viewportPosition.Position;
+        }
+
         protected virtual void OnViewportChanged()
         {
             Map parentMap = ParentMap;
@@ -140,42 +130,59 @@ namespace MapControl
 
         private static void LocationPropertyChanged(DependencyObject obj, DependencyPropertyChangedEventArgs eventArgs)
         {
-            UIElement element = (UIElement)obj;
-            Location location = (Location)eventArgs.NewValue;
-            Map parentMap;
+            UIElement element = obj as UIElement;
 
-            if (location != null && (parentMap = GetParentMap(element)) != null)
+            if (element != null)
             {
-                SetViewportPosition(element, parentMap, location);
-            }
-            else
-            {
-                element.ClearValue(ViewportPositionPropertyKey);
-                element.ClearValue(IsInsideMapBoundsPropertyKey);
-                element.Arrange(new Rect());
+                SetViewportPosition(element, GetParentMap(element), (Location)eventArgs.NewValue);
             }
         }
 
         private static void SetViewportPosition(UIElement element, Map parentMap, Location location)
         {
-            Point viewportPosition = parentMap.LocationToViewportPoint(location);
+            ViewportPosition viewportPosition = null;
+
+            if (parentMap != null && location != null)
+            {
+                Point position = parentMap.LocationToViewportPoint(location);
+
+                viewportPosition = new ViewportPosition(position,
+                    position.X >= 0d && position.X <= parentMap.ActualWidth &&
+                    position.Y >= 0d && position.Y <= parentMap.ActualHeight);
+            }
 
             element.SetValue(ViewportPositionPropertyKey, viewportPosition);
-            element.SetValue(IsInsideMapBoundsPropertyKey,
-                viewportPosition.X >= 0d && viewportPosition.X <= parentMap.ActualWidth &&
-                viewportPosition.Y >= 0d && viewportPosition.Y <= parentMap.ActualHeight);
-
-            ArrangeElement(element, viewportPosition);
         }
 
-        private static bool ArrangeElement(UIElement element, Point position)
+        private static void ViewportPositionPropertyChanged(DependencyObject obj, DependencyPropertyChangedEventArgs eventArgs)
         {
+            UIElement element = obj as UIElement;
+
+            if (element != null)
+            {
+                ViewportPosition position = (ViewportPosition)eventArgs.NewValue;
+
+                if (position != null)
+                {
+                    ArrangeElement(element, position);
+                }
+                else
+                {
+                    element.Arrange(new Rect());
+                }
+            }
+        }
+
+        private static bool ArrangeElement(UIElement element, ViewportPosition viewportPosition)
+        {
+            MapPanel panel = VisualTreeHelper.GetParent(element) as MapPanel;
+            Point position = panel != null ? panel.GetArrangePosition(viewportPosition) : viewportPosition.Position;
             Rect rect = new Rect(position, element.DesiredSize);
             FrameworkElement frameworkElement = element as FrameworkElement;
 
             if (frameworkElement != null)
             {
-                if (frameworkElement.HorizontalAlignment == HorizontalAlignment.Stretch &&
+                if (frameworkElement.HorizontalAlignment == HorizontalAlignment.Stretch ||
                     frameworkElement.VerticalAlignment == VerticalAlignment.Stretch)
                 {
                     return false; // do not arrange at position
diff --git a/MapControl/Themes/Generic.xaml b/MapControl/Themes/Generic.xaml
index 1409c6d7..99c85ced 100644
--- a/MapControl/Themes/Generic.xaml
+++ b/MapControl/Themes/Generic.xaml
@@ -11,6 +11,8 @@
         </Setter>
     </Style>
     <Style x:Key="{x:Type map:MapItem}" TargetType="{x:Type map:MapItem}">
+        <Setter Property="HorizontalAlignment" Value="Center"/>
+        <Setter Property="VerticalAlignment" Value="Center"/>
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="{x:Type map:MapItem}">
diff --git a/MapControl/ViewportPosition.cs b/MapControl/ViewportPosition.cs
new file mode 100644
index 00000000..ebe1940a
--- /dev/null
+++ b/MapControl/ViewportPosition.cs
@@ -0,0 +1,23 @@
+// WPF MapControl - http://wpfmapcontrol.codeplex.com/
+// Copyright © 2012 Clemens Fischer
+// Licensed under the Microsoft Public License (Ms-PL)
+
+using System.Windows;
+
+namespace MapControl
+{
+    /// <summary>
+    /// Viewport position of a MapPanel child element.
+    /// </summary>
+    public class ViewportPosition
+    {
+        public ViewportPosition(Point position, bool isInside)
+        {
+            Position = position;
+            IsInside = isInside;
+        }
+
+        public Point Position { get; private set; }
+        public bool IsInside { get; private set; }
+    }
+}
diff --git a/SampleApps/SampleApplication/MainWindow.xaml b/SampleApps/SampleApplication/MainWindow.xaml
index 52c7b01c..9d2bad55 100644
--- a/SampleApps/SampleApplication/MainWindow.xaml
+++ b/SampleApps/SampleApplication/MainWindow.xaml
@@ -65,7 +65,7 @@
         </Style>
         <Style x:Key="PushpinItemStyle" TargetType="map:MapItem">
             <Setter Property="map:MapPanel.Location" Value="{Binding Location}"/>
-            <Setter Property="Visibility" Value="{Binding (map:MapPanel.IsInsideMapBounds), Converter={StaticResource BooleanToVisibilityConverter}, RelativeSource={RelativeSource Self}}"/>
+            <Setter Property="Visibility" Value="{Binding (map:MapPanel.ViewportPosition).IsInside, Converter={StaticResource BooleanToVisibilityConverter}, RelativeSource={RelativeSource Self}}"/>
             <Setter Property="HorizontalAlignment" Value="Left"/>
             <Setter Property="VerticalAlignment" Value="Bottom"/>
             <Setter Property="Template">
@@ -103,7 +103,7 @@
                                  ItemContainerStyle="{StaticResource PushpinItemStyle}"
                                  IsSynchronizedWithCurrentItem="True"/>
             <map:Pushpin Location="53.5,8.2" Background="Yellow" Foreground="Blue" Content="N 53° 30' E 8° 12'"
-                         Visibility="{Binding (map:MapPanel.IsInsideMapBounds), Converter={StaticResource BooleanToVisibilityConverter}, RelativeSource={RelativeSource Self}}"/>
+                         Visibility="{Binding (map:MapPanel.ViewportPosition).IsInside, Converter={StaticResource BooleanToVisibilityConverter}, RelativeSource={RelativeSource Self}}"/>
             <TextBlock HorizontalAlignment="Left" VerticalAlignment="Bottom" Margin="2,0,0,0" FontSize="10"
                        Text="{Binding MainTileLayer.Description, ElementName=map}"/>
         </map:Map>
@@ -119,7 +119,7 @@
                 <Slider Name="headingSlider" ToolTip="Heading" Margin="4,0,4,0" Width="100" Minimum="0" Maximum="360" SmallChange="10" LargeChange="45"
                         Value="{Binding TargetHeading, ElementName=map}"/>
                 <CheckBox ToolTip="Map Overlay" Margin="4,0,4,0" VerticalAlignment="Center" Content="Seamarks" Click="SeamarksClick"/>
-                <ComboBox Name="tileLayerComboBox" ToolTip="Main Tile Layer" Margin="4,0,4,0" DisplayMemberPath="Name" SelectedIndex="0">
+                <ComboBox Name="tileLayerComboBox" ToolTip="Main Tile Layer" Margin="4,0,0,0" DisplayMemberPath="Name" SelectedIndex="0">
                     <ComboBox.Items>
                         <map:TileLayer Name="OpenStreetMap" Description="© {y} OpenStreetMap Contributors, CC-BY-SA"
                                        TileSource="http://{c}.tile.openstreetmap.org/{z}/{x}/{y}.png"/>
diff --git a/SampleApps/SampleApplication/MainWindow.xaml.cs b/SampleApps/SampleApplication/MainWindow.xaml.cs
index 805cacbb..01afc270 100644
--- a/SampleApps/SampleApplication/MainWindow.xaml.cs
+++ b/SampleApps/SampleApplication/MainWindow.xaml.cs
@@ -1,7 +1,9 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Input;
+using System.Windows.Threading;
 using Caching;
 using MapControl;
 
@@ -9,6 +11,12 @@ namespace SampleApplication
 {
     public partial class MainWindow : Window
     {
+        private SamplePoint movingPoint = new SamplePoint
+        {
+            Name = "Moving",
+            Location = new Location(53.5, 8.25)
+        };
+
         public MainWindow()
         {
             if (Properties.Settings.Default.UsePersistentCache)
@@ -67,6 +75,7 @@ namespace SampleApplication
                     Name = "Buhne 10",
                     Location = new Location(53.49350, 8.15563)
                 });
+            points.Add(movingPoint);
 
             ICollection<object> pushpins = (ICollection<object>)Resources["Pushpins"];
             pushpins.Add(
@@ -93,6 +102,22 @@ namespace SampleApplication
                     Name = "Eckwarderhörne",
                     Location = new Location(53.5207, 8.2323)
                 });
+
+            DispatcherTimer timer = new DispatcherTimer();
+            timer.Interval = TimeSpan.FromSeconds(0.05);
+            timer.Tick += MovePoint;
+            timer.Start();
+        }
+
+        private void MovePoint(object sender, EventArgs e)
+        {
+            movingPoint.Location = new Location(movingPoint.Location.Latitude + 0.0005, movingPoint.Location.Longitude + 0.001);
+
+            if (movingPoint.Location.Latitude > 54d)
+            {
+                movingPoint.Name = "Stopped";
+                ((DispatcherTimer)sender).Stop();
+            }
         }
 
         private void MapManipulationInertiaStarting(object sender, ManipulationInertiaStartingEventArgs e)
diff --git a/SampleApps/SampleApplication/SampleItems.cs b/SampleApps/SampleApplication/SampleItems.cs
index 2f91a734..ab445b3b 100644
--- a/SampleApps/SampleApplication/SampleItems.cs
+++ b/SampleApps/SampleApplication/SampleItems.cs
@@ -1,12 +1,43 @@
 using System.Collections.ObjectModel;
 using MapControl;
+using System.ComponentModel;
 
 namespace SampleApplication
 {
-    class SamplePoint
+    class SamplePoint : INotifyPropertyChanged
     {
-        public string Name { get; set; }
-        public Location Location { get; set; }
+        private string name;
+        private Location location;
+
+        public event PropertyChangedEventHandler PropertyChanged;
+
+        public string Name
+        {
+            get { return name; }
+            set
+            {
+                name = value;
+                OnPropertyChanged("Name");
+            }
+        }
+
+        public Location Location
+        {
+            get { return location; }
+            set
+            {
+                location = value;
+                OnPropertyChanged("Location");
+            }
+        }
+
+        private void OnPropertyChanged(string propertyName)
+        {
+            if (PropertyChanged != null)
+            {
+                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
+            }
+        }
     }
 
     class SamplePolyline