Belle Fourche River

The Belle Fourche River (prounced "bel FOOSH") is a tributary of the Cheyenne River, about long, in the U.S. states of Wyoming and South Dakota. It is part of the Mississippi River watershed traveling through the Cheyenne and Missouri rivers.
The point at which the river flows out of Wyoming and into South Dakota is the lowest elevation point in the state of Wyoming at . This is the second-highest low point of any U.S. state.