<P> Rising out of the marshy western end of Great Slave Lake , the Mackenzie River flows generally west - northwest for about 300 km ( 190 mi ) , passing the hamlet of Fort Providence . At Fort Simpson it is joined by the Liard River , its largest tributary , then swings towards the Arctic , paralleling the Franklin Mountains as it receives the North Nahanni River . The Keele River enters from the left about 100 km ( 62 mi ) above Tulita , where the Great Bear River joins the Mackenzie . Just before crossing the Arctic Circle , the river passes Norman Wells , then continues northwest to merge with the Arctic Red and Peel rivers . It finally empties into the Beaufort Sea , part of the Arctic Ocean , through the vast Mackenzie Delta . </P>
where does the mackenzie river start and end
Rising out of the marshy western end of Great Slave Lake empties into the Beaufort Sea , part of the Arctic Ocean , through the vast Mackenzie Delta