River, rising in central Colorado, U.S. At 1,450 mi (2,333 km) long, it flows east through southern Kansas and southeast across northeastern Oklahoma and bisects Arkansas, where it empties into the Mississippi River .
Navigable for 650 mi (1,046 km), its largest tributaries are the Canadian and Cimarron rivers. It is believed to have been crossed by Francisco Vazquez de Coronado in 1541 near the site of Dodge City, Kan., and by Zebulon Pike in 1806.