In 1934, the construction of the highway Berlin - Königsberg began. Work was started on both sides simultaneously, but was never completed. The plan provided that the motorway would cross Dłusko Lake. Instead of building a long bridge, it was decided to fill the lake, leaving only a narrow isthmus, over which a short bridge was to appear. The earthworks have been done, but not the bridge. Today, Dłusko Lake is crossed by a wide, wooded causeway with steep descents to the water.