The Thelon River stretches 900 kilometres (560 mi) across northern Canada. Its source is Whitefish Lake in the Northwest Territories, and it flows east to Baker Lake in Nunavut. The Thelon ultimately drains into Hudson Bay at Chesterfield Inlet.

Beverly Lake is a lake in the Kivalliq Region, Nunavut, Canada. It is located north of the Arctic tree line about 150 km (93 mi) northwest of Baker Lake, Nunavut. The western half of the lake is within Thelon Wildlife Sanctuary. The Thelon River, at the confluence with the Dubawnt River, empties into the lake's southwestern bank. The Kazan River empties into the Thelon River at Beverly Lake's southeastern bank, between Beverly and Aberdeen Lakes. A delta occurs on the Beverly Lake's southern edge, which includes the Isarurjuaq Peninsula.