Lake, northwestern Russia. Located between Lake Ladoga and the White Sea, it is the second-largest lake in Europe. It has an area of 3,753 sq mi (9,720 sq km) and is 154 mi (248 km) long. It empties into the Svir River and is frozen for about half of each year. It is connected with the Baltic and White seas by canal and with the Volga River basin by a waterway, enabling it to play an important part in international trade and transport.
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