Kama (käˈmə) [key], river, c.1,260 mi (2,030 km) long, E European Russia, the chief left tributary of the Volga. It rises in the foothills of the central Urals and flows N, then E, and then SW past Perm, Sarapul, and Chistopol to join the Volga below Kazan. The Vyatka is its principal tributary. The Kama is an important transportation artery. There is a large hydroelectric station at Perm.