River, southern Saskatchewan, Canada.
It is about 270 mi (435 km) long and flows east through several lakes and Indian reservations and across the Manitoba border into the Assiniboine River . Its French name, meaning "who calls," derived from its Cree Indian name Kah-tep-was ("River That Calls"), referring to the cries of a legendary spirit supposedly haunting its waters. Once a fur-trapping region, its basin is now farmed for wheat.