About 1,470 miles · CO, KS, OK, AR · source near Leadville, CO · mouth Mississippi River
Arkansas River map
The Arkansas rises near Leadville, Colorado, and flows about 1,470 miles through Kansas, Oklahoma and Arkansas to the Mississippi. It is the longest tributary in the Mississippi–Missouri system after the Missouri itself.
Where the Arkansas is
The river starts in the Sawatch and Mosquito ranges above Leadville, Colorado, at about 10,000 ft, and drops through the Royal Gorge near Cañon City before reaching the plains at Pueblo. It crosses southeastern Colorado and southern Kansas, bends south through Oklahoma past Tulsa, and crosses Arkansas from Fort Smith to the Mississippi near Napoleon, about 40 miles below Pine Bluff. At about 1,470 miles it ranks around fifth or sixth among US rivers.
States along the river
- Colorado — the headwaters, Royal Gorge and Pueblo; the upper river is one of the busiest rafting stretches in the country.
- Kansas — Garden City, Dodge City, Great Bend (named for the river's turn), Hutchinson and Wichita; in Kansas the name is pronounced "ar-KAN-zas".
- Oklahoma — Tulsa, Muskogee and Fort Gibson; the Keystone and Kaw reservoirs.
- Arkansas — Fort Smith, Dardanelle, Little Rock and Pine Bluff.
Key measurements
- Length: about 1,470 miles; basin about 170,000 square miles.
- Main tributaries: the Cimarron and Canadian (both from the west, joining in Oklahoma), the Verdigris and Neosho (from Kansas), and the Purgatoire in Colorado.
- The Royal Gorge is about 1,000 ft deep at the suspension bridge, which was the world's highest when it opened in 1929.
- The McClellan–Kerr Arkansas River Navigation System (1971) gives barges a channel from the Mississippi to the Port of Catoosa near Tulsa, 445 miles inland, through 18 locks and dams.
- In western Kansas the riverbed is dry for much of the year because Colorado and Kansas irrigation removes the flow; Kansas won a long Supreme Court case over this in 1995.
Cities on the river
Pueblo and Colorado Springs (on Fountain Creek, a tributary) in Colorado; Wichita, the largest city in Kansas; Tulsa, which grew on the river's oil fields; Fort Smith on the Oklahoma line; and Little Rock, the capital of Arkansas, named for a rock outcrop on the bank. Oklahoma City is on the North Canadian, a tributary.
How the river shaped the map
The 1819 Adams–Onís Treaty with Spain used the Arkansas River as part of the boundary between the US and New Spain, from its mouth on the 100th meridian upstream to its source, then north to the 42nd parallel. That is why the river appears on every early map of the Louisiana Purchase. The river divides Oklahoma diagonally: the northeast is Ozark and prairie country, the southwest is plains. In Arkansas it separates the Ozarks to the north from the Ouachita Mountains to the south.
Related maps
- Mississippi River — where the Arkansas ends.
- Rocky Mountains — the source.
- Great Plains and Ozarks — the country it crosses.
- Longest US rivers · All geography maps.