The
Koporye Bay (
Russian: Копорская губа,
Koporskaya Guba) is a 12 km-long
bay on the southern coast of the
Gulf of Finland. It is up to 26 km wide and 20 meters deep. The shore is low and rocky; the hinterland is woody. It is part of
Russia's
Leningrad Oblast. The only major settlement is the town of
Sosnovy Bor. The Voronka and Sista Rivers drain into the bay. It is named after the medieval fortress of
Koporye which lies slightly to the south.