The Coppermine River is a river in the North Slave and Kitikmeot regions of the Northwest Territories and Nunavut in Canada. It is 845 kilometres (525 mi) long. It rises in Lac de Gras, a small lake near Great Slave Lake, and flows generally north to Coronation Gulf, an arm of the Arctic Ocean. The river freezes in winter but may still flow under the ice. The community of Kugluktuk (formerly Coppermine) is located at the river's mouth.