Mackenzie River: North America's Longest River System

Yes, the Mackenzie River is in North America. It is Canada's longest river system (4,241 km / 2,635 mi including tributaries) and the second‑largest drainage basin in North America (after the Mississippi). It flows northwest through the Northwest Territories and Nunavut, draining the eastern slopes of the Rockies and the interior plains, and empties into the Beaufort Sea (Arctic Ocean). It is navigable in summer and vital for northern communities and resource transport.