Vazuza (Russian: Вазу́за) is a river in Smolensk Oblast and Tver Oblast, Russia, a right tributary of the Volga River. Length: 162 km, watershed area: 7120 km². The lower part of the river has been transformed into Vazuza Reservoir. The towns of Sychyovka and Zubtsov are located on the Vazuza (the latter at its confluence with the Volga).
Coordinates: 56°10′05″N 34°35′27″E / 56.1681°N 34.5908°E / 56.1681; 34.5908