The Moskva River (Russian: река Москва, Москва-река, Moskva-reka), also known as the Moscow River, is a river of western Russia. It rises about 140 km (90 mi) west of Moscow, and flows roughly east through the Smolensk and Moscow Oblasts, passing through central Moscow. About 110 km (70 mi) south east of Moscow, at the city of Kolomna, it flows into the Oka River, itself a tributary of the Volga, which ultimately flows into the Caspian Sea.