Red River (United States)

Red River (United States), river, southern U.S., formed in southwestern Oklahoma by the junction of the North Fork and the Prairie Dog Town Fork (which flows from Texas). It flows east, forming the Oklahoma-Texas border, then south through Arkansas and southeast through Louisiana, to the Mississippi River. It is the southernmost of the large tributaries of the Mississippi and discharges into the Gulf of Mexico by way of the Atchafalaya River in Louisiana. The Red River is 1,970 km (1,220 mi) long, and its drainage area, including its tributaries, is about 236,725 sq km (about 91,400 sq mi). The chief tributaries are the Wichita, Washita, Kiamichi, and Sulphur rivers. The largest city on the Red River is Shreveport, Louisiana.