1) Strait of the Baltic Sea 
Drogden is a channel through the Sound designed for shipping. The trench is located on the Danish side of the Øresund, between Saltholm and Amager. It passes over the Øresund Bridge, whose lowest point is located right there. Maximum depth of ships that can pass is 8.0 metres. Drogden is heavily trafficked. It passes about 30 000 ships per year ...