Lake astride the Canadian-U.S. boundary, southwestern Ontario, southeastern Manitoba, and northern Minnesota.
Irregular in shape, it is 70 mi (110 km) long and up to 60 mi (95 km) wide. It has an area of 1,727 sq mi (4,472 sq km), of which 642 sq mi (1,663 sq km) are in U.S territory. It has an estimated 25,000 mi (40,000 km) of shoreline and more than 14,000 islands. It receives the Rainy River from the southeast and drains north through the Winnipeg River into Lake Winnipeg . Visited by French explorers in 1688, it became an important fur-trading route between the Great Lakes and western Canada. The Northwest Angle, the northernmost point of the coterminous U.S., is separated from the rest of Minnesota by a part of the lake.