range of hills on the Russian Plain, western Russia. The hills form the watershed between the left-bank tributaries of the Volga River and of the Sukhona, Yug, Vychegda, and Pechora rivers. The hills run east-west for 375 miles (600 km), reach a maximum height of 965 feet (294 m), and consist mainly of morainic sands and clays, swampy in sections with occasional coniferous woodlands.