<P> The Red River is the second - largest river basin in the southern Great Plains . It rises in two branches in the Texas Panhandle and flows east , where it acts as the border between the states of Texas and Oklahoma . It forms a short border between Texas and Arkansas before entering Arkansas , turning south near Fulton , Arkansas , and flowing into Louisiana , where it flows into the Atchafalaya River . The total length of the river is 1,360 miles ( 2,190 km ) , with a mean flow of over 57,000 cubic feet per second ( 1,600 m / s ) at the mouth . </P>
where does the red river start and end in louisiana
the Texas Panhandle