It rises in on the northern slope of the Big Sheep Mountains, in northwestern Prairie County, and flows northeast across the plains past Brockway and Circle and joins the Missouri in northeastern McCone County, approximately 4 mi (6.4 km) south of Poplar.
The Missouri River is a tributary of the Mississippi River in the United States.
During the late 19th century, the river was a primary means of transportation of goods and passengers before the spread of the railroads.
Rivers of the United States Borders Maritime Claims Forty-nine states in the United States (all except Hawaii) lie on the North American continent; 48 of these (all except Alaska) are contiguous and form the continental United States.