The second largest lake in Europe, situated in the northwest part of the European portion of Russia, between Lake Ladoga and the White Sea. It covers an area of 3,753 square miles (9,720 square km). It is 154 miles (248 km) long; its greatest width is 50 miles (80 km); and its greatest depth is about 380 feet (116 m). The hollow of the lake was formed by movements of the Earth's crust, but Quaternary glaciers (those from the past 2. 6 million years) elongated it from northwest to southeast.