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.