The Assiniboine River, chief tributary of the Red River which it joins in the City of Winnipeg, takes its name from the Assiniboine Indians through whose hunting grounds it flowed. The river rises in the Province of Saskatchewan and is approximately 600 miles in length. A number of trading posts were established along its banks by the North West, XY and Hudson's Bay companies, and on its waters plied canoes, York boats, and stern wheel steamers. The first post along its banks was built in 1738 by French explorer La Verendrye on his first journey west, who called it the St. Charles River.