Obsha
Obsha
a river in Kalinin Oblast, RSFSR; rises on the border with Smolensk Oblast. Left tributary of the Mezha River (Zapadnaia Dvina basin). Length, 153 km; basin area, 2,080 sq km. The Obsha rises on the Belyi Upland. It is fed mainly by snow. The average discharge 47 km from the mouth is 11.5 cu m per sec. The river freezes in November and opens up in late March or April. The city of Belyi is located on the river.