Slave River

River in Alberta and the Northwest Territories, flowing north from Lake Athabasca to the Great Slave Lake; length 420 km/260 mi. The Slave River forms an upper part of a continuous waterway that follows the Mackenzie River lowlands. The river is named after the Slavey, a division of the Dene indigenous people.

From the southwestern end of Lake Athabasca, the Slave River follows a generally northerly course; 32 km/20 mi after leaving the lake, the Peace River joins it from the west. Continuing north, it enters the Northwest Territories, on the southwestern edge of the Canadian Shield, running past Fort Smith to the Great Slave Lake, which it enters through a delta. Near Fort Smith the Pelican Rapids, an ancient portage site, have been the focus of controversy over a scheme to generate hydroelectric energy.