Mackenzie River great depths to bedrock. A characteristic feature of the delta is its numerous pingos, or hills of earth-covered-ice – some 1,400 of them. The Peel River, carrying much of the runoff from the northern Yukon, joins in the delta at a point northeast of Fort McPherson. Below there, the Mackenzie diverges into several large channels with the largest heading north-northeast, emptying into the Beaufort Sea west of Tuktoyaktuk. At , the Mackenzie River drainage basin encompasses nearly 20 percent of Canada. About , or 54 percent of the basin, lies above Great Slave Lake. Permafrost underlies about three-quarters of the
Steamboats of the Peace River Steamboats of the Peace River The Peace River, which flows from the Rocky Mountains in British Columbia to the Peace–Athabasca Delta and Lake Athabasca in Alberta, was navigable by late nineteenth and early twentieth century steamboats from the Rocky Mountain Falls at Hudson's Hope to Fort Vermilion, where there was another set of rapids, then via the lower Peace from Vermilion to Lake Athabasca. The Peace is part of the Mackenzie Basin, a larger river complex which includes the Athabasca, Slave, and Mackenzie Rivers. The Athabasca had large rapids too at Grande Rapids and Fort Smith; in this way the