The Strelasund or Strela Sound is a sound or lagoon of the Baltic Sea which separates Rügen from the German mainland. It is crossed by a road and rail bridge called the Rügendamm in Stralsund. It runs northwest to southeast from a small shallow bay just north of Stralsund called the Kubitzer Bodden through to another such bay, the Greifswalder Bodden in the southeast. The sound is nowhere much more than 3 km wide, reaching its greatest width towards its southeast end. It is roughly 25 km long.