public ReadOnlyObservableCollection<Bookmark> GetBookmarks()

{
  //Create a map frame and set its camera by zooming to the extent of an existing bookmark.
  //Construct on the worker thread

  //Build 2D envelope geometry
  Coordinate2D mf_ll = new Coordinate2D(6.0, 8.5);
  Coordinate2D mf_ur = new Coordinate2D(8.0, 10.5);
  Envelope mf_env = EnvelopeBuilderEx.CreateEnvelope(mf_ll, mf_ur);

  //Reference map, create MF and add to layout
  MapProjectItem mapPrjItem = Project.Current.GetItems<MapProjectItem>()
                       .FirstOrDefault(item => item.Name.Equals("Map"));
  Map mfMap = mapPrjItem.GetMap();
  Bookmark bookmark = mfMap.GetBookmarks().FirstOrDefault(
                        b => b.Name == "Great Lakes");

  MapFrame mfElm = ElementFactory.Instance.CreateMapFrameElement(
                       layout, mf_env, mfMap, "New Map Frame");

  //Zoom to bookmark
  mfElm.SetCamera(bookmark);
}

{
  // Note: Needs QueuedTask to run
  {
    //Return the collection of bookmarks for the map.
    var result = mapView.Map.GetBookmarks();
    // Use the bookmarks (if any)
  }
}

{
  // Note: Needs QueuedTask to run
  {
    //Get the first bookmark with the given name.
    var bookmark = mapView.Map.GetBookmarks().FirstOrDefault(b => b.Name == bookmarkName);
    if (bookmark == null)
    {
      // Manage the error - bookmark not found
    }

    //Zoom the view to the bookmark.
    mapView.ZoomTo(bookmark);
  }
}

{
  // Note: Needs QueuedTask to run
  //Get the first bookmark with the given name.
  var bookmark = mapView.Map.GetBookmarks().FirstOrDefault(b => b.Name == bookmarkName);
  if (bookmark == null)
  {
    // Manage the error - bookmark not found
  }

  //Zoom the view to the bookmark.
  mapView.ZoomToAsync(bookmark, TimeSpan.FromSeconds(2));
}

{
  //Get the collection of bookmarks for the project.
  var result = Project.Current.GetBookmarks();
  // Use the bookmarks (if any)
}

{
  // Note: Needs QueuedTask to run
  {
    //Find the first bookmark with the name
    var bookmark = mapView.Map.GetBookmarks().FirstOrDefault(b => b.Name == bookmarkName);
    if (bookmark == null)
    {
      //Bookmark not found
    }

    //Remove the bookmark
    mapView.Map.RemoveBookmark(bookmark);
  }
}