Arkansas River
Rocky Mountain river crossing the plains to the Mississippi
The Arkansas River begins as a snowmelt stream near Leadville, Colorado, at about 9,700 feet (2,965 m), and ends 1,469 miles (2,364 km) later at the Mississippi River in the cotton country of southeastern Arkansas. That makes it the sixth-longest river in the United States and the second-longest tributary in the Mississippi-Missouri system. Few rivers change character so completely. In Colorado it is a whitewater river that cuts the more than 1,000-foot-deep Royal Gorge, on the Kansas plains it can shrink to a sandy, braided channel, and below Tulsa it becomes a working waterway.
For two centuries the river was a frontier. The 1819 Adams-Onís Treaty made the upper Arkansas part of the boundary between the United States and Spanish territory, and travelers on the Santa Fe Trail followed its valley across Kansas. The name comes from a French rendering of a word for the Quapaw people who lived near its mouth. The McClellan-Kerr Arkansas River Navigation System, built by the Army Corps of Engineers between 1963 and 1970, uses locks and dams to carry barges from the Mississippi to the Port of Catoosa near Tulsa. Cities along the way include Pueblo, Wichita, Tulsa and Little Rock.