The red river is an important texas watershed as it is the second largest river basin in the southern great planes.
The red river or sometimes the red river of the south was named for its reddish watercolor passing through red bed country in its watershed. it also forms a short border between texas and Arkansas before entering Arkansas. The south bank of the red river formed part of the US-Mexico border from the Adams onis treaty.
Tributaries of the red river include the salt fork red river, little red river, prairie dog town fork red river, north fork red river, Kiamichi river, Wichita river, sulfur river, etc.
These were some major tributaries of the red river.