Wister Lake and Dam on the Poteau River in Le Flore County, Oklahoma
The Poteau River is a 141-mile-long (227 km) river in the U.S. states of Arkansas and Oklahoma and is the only river in Oklahoma that flows north. Poteau is the French word for "post" and it is believed the river was named because French explorers used a post or stake to mark the mouth of the river. The city of Poteau, Oklahoma took its name from the river. The Poteau River converges with the Arkansas River at Belle Point at Fort Smith, Arkansas, where it serves as a border between the two states for a short distance.