Horn River formed along the middle course of the Horn River, and is followed downstream by the "Second Lake". The river turns south-west, where the "Mink Lake" is formed along its course. The Laferte River also flows into the Mink Lake. Horn River then flows south, and it receives the waters of the Bluefish River before it empties into the Mackenzie River, downstream from the Great Slave Lake), immediately upstream from Mills Lake, at an elevation of . The arch made by the river defines the "Horn Plateau", a flat elevated area that rises up to ) to the north and east,
Christina Lake (Alberta) River at its western end. The Jackfish River flows before it empties into the Christina River, a tributary of the Clearwater River. The waters eventually reach the Arctic Ocean via the Athabasca and MacKenzie Rivers. Christina Lake and the Christina River were named to honour Christine Gordon, originally from Scotland, who was the first white woman to live permanently in the Fort McMurray area, where she remained until her death in the 1940s. She was highly respected by the community, including the First Nations and Métis. Gordon, partly based on knowledge gleaned from a Scottish home nursing book, made her