Mackenzie River Mackenzie River The Mackenzie River (Slavey language: Deh-Cho , "big river" or Inuvialuktun: Kuukpak , "great river"; ) is the longest river system in Canada, and has the second largest drainage basin of any North American river after the Mississippi River. The Mackenzie River flows through a vast, thinly populated region of forest and tundra entirely within the Canadian Northwest Territories, although its many tributaries reach into four other Canadian provinces and territories. The river's main stem is long, flowing north-northwest from Great Slave Lake into the Arctic Ocean, where it forms a large delta at its mouth. Its extensive
Mackenzie River Bear River, the outflow of Great Bear Lake at Tulita. The Mackenzie widens considerably to about at Norman Wells, a major center of oil production. There is a narrows at the Mountain River confluence called the Sans Sault Rapids, where the Mackenzie falls about . Below the Mountain River the Mackenzie flows due north until reaching The Ramparts, a limestone gorge barely wide and up to deep. Below The Ramparts is the village of Fort Good Hope, where the Mackenzie turns northwest again, soon crossing the Arctic Circle. The Mackenzie here flows slightly lower in elevation than the surrounding tundra,