Langenwerder is a small uninhabited island near the island Poel north of Gollwitz, a district of the municipality of Poel island.
It is approximately 800 metres long, 500 metres wide, and flat.
The island is a nature reserve, due to the birds that live there, and therefore access to the island is not usually allowed.
Wikipedia https://en.wikipedia.org/wiki/Langenwerder
Official Website http://www.langenwerder.de/
Coordinates 54°1'40.769" N 11°29'37.905" E