It's the Royal Gorge Bridge over the Arkansas River.
hmm... maybe you are asking this question because you drove over that bridge in Ft. Smith where the Arkansas River bends on the state line. In that case it would be the Arkansas River, however with the exception of that one location there is no river that separates Arkansas and Oklahoma.
The red river
Mississippi.
The state that is drained by the Arkansas and Red river is Oklahoma.
There are several tributaries to the Mississippi River. Five of these tributaries are the Missouri, Ohio, Arkansas, Black, and Red Rivers.
The Red River (Mississippi River) forms a border between Texas and Oklahoma. It is a short border between Texas and Arkansas before entering Arkansas, turning south near Fulton, Arkansas and flowing into Louisiana. The total length of the river is 1,360 miles (2,190 km).
The three rivers that flow out of Arkansas into Louisiana are the Ouachita River, the Red River, and the Mississippi River. The Ouachita River runs southward, eventually joining the Red River. The Red River serves as a significant waterway between the two states, while the Mississippi River forms the eastern boundary of Arkansas and flows south into Louisiana.
Arkansas, the Canadian, and the Red.
Red Bridge - Tasmania - was created in 1838.
Red Cliff Bridge was created in 1940.
Red Wing Bridge was created in 1960.