Great Bear Lake is the largest lake entirely within Canada (Lake Superior and Lake Huron straddling the Canada-US border are larger), the fourth largest in North America, and the seventh largest in the world. The lake is in the Northwest Territories and is situated on the Arctic Circle between 65 and 67 degrees of northern latitude and between 118 and 123 degrees western longitude, 186 m (610 ft) above sea level.
The lake has a surface area of 31,153 km2 (12,028 sq mi) and a total volume of 2,236 km3 (536 cu mi). Its maximum depth is 446 m (1,463 ft) and its average depth 71.7 m (235 ft). The total shoreline is 2,719 km (1,690 mi) and the total catchment area of the lake is 114,717 km2 (44,292 sq mi). The lake empties through the Great Bear River (Sahtúdé) into the Mackenzie River. This lake is surrounded by boreal forest, although the Arctic tundra border lies within 100 mi (160 km) north.
Fishing is an important income source and there are five fishing lodges located around the lake. One of which, Plummers Great Bear Lake Lodge which is located on the Dease Arm just north of the Arctic Circle, operate both Great Bear Lake Airport and Great Bear Lake Water Aerodrome. In 1995, a 32.8 kg (72.3 lb) lake trout, the largest ever caught with a rod and reel, was taken on the lake.