The world's strongest tidal current is near the Norwegian city of Bodø. It impresses with its large whirlpools, which produce water masses reaching speeds of almost 40 km/h.
The Herrenhaus Oppenheim am Fühlinger See is an interesting Lost Place in the district of Cologne. It was built in the late 19th century next to a racecourse and is the source of all sorts of ghost stories.