Mstino

a lake in Kalinin Oblast, RSFSR, in the northeastern Valdai Hills (Vyshnii Volochek Chain). Area, 12.5 sq km; length, approximately 10 km; width, 1.5–2 km; depths, to 10 m. The lake extends from south-southeast to north-northwest. It is fed by mixed sources, mainly snow. The Tsna and Shlina rivers empty into Lake Mstino. The lake is also the source of the Msta River. It was transformed into a reservoir when the Vyshnii Volok Water System was constructed.