The Tvertsa is a river in Vyshnevolotsky, Spirovsky, Torzhoksky, and Kalininsky Districts, as well as in the cities of Torzhok and Tver in Tver Oblast, Russia, a left tributary of the Volga River. It is long, and the area of its basin . The principal tributaries of the Tvertsa are the Tigma River (left), the Shchegrinka River (right), the Osuga River (right), the Logovyazh River (left), and the Kava River (left).