One of the really interesting parts of the Ohio is on the Indiana side just across from Louisville. Its called the Falls of the Ohio and there is a museum and a path to walk down to see for yourself whats left of a big rapids that existed there.
I guess it was a miserable place for boatsman way back when to get upstream.
You can see eons of civilization unearthed by the river.
They have since built a dam and built up enough water for the towboats to traverse but you can still see a lot of river bottom.