The Rio Grande River
The Colorado River forms part of the southwest boundary of the United States.
The Rio Grande River
The Colorado River
The Colorado river
The Rio Grande River (Rio Bravo as known in Mexico) forms a natural boundary between the southwestern United States and Mexico; however it is not a waterway as the river is not navigable.
The Mississippi river forms the boundary between Missouri and Illinois!
The Ohio River forms the boundary between Indiana and Kentucky.
The Red river forms Texas southwest. The Rio Grande forms the southwest border between Texas and Mexico.
The Potomac river
The Ohio River forms Ohio's southern boundary. It serves as a natural border between Ohio and West Virginia, as well as Kentucky. This river is a significant waterway in the United States, flowing westward before joining the Mississippi River.
The Connecticut River
red river