Udomlya is a town and the administrative center of Udomelsky District in Tver Oblast, Russia, located on the shores of Lake Pesvo on the Rybinsk–Bologoye railway, 225 kilometers (140 mi) north of Tver, the administrative center of the oblast. Population: 31,061 (2010 Census); 31,961 (2002 Census); 30,751 (1989 Soviet census).