Osuga

a river in Kalinin Oblast, RSFSR, a right tributary of the Tvertsa River (Volga Basin). The Osuga is 167 km long and drains an area of 2,410 sq km. It rises in the Valdai Hills and meanders in great loops. It is fed mainly by snow. The river freezes in November, and the ice breaks up in April. Timber is floated down the river. The city of Kuvshinovo is situated on the Osuga.