Cumberland River, a branch of the Ohio River, rises in the Cumberland Mountains in eastern Kentucky. From there, it winds southwestward into central Tennessee, then northwestward into western Kentucky. It empties into the Ohio at Smithland, Kentucky. The Cumberland is about 690 miles (1,100 kilometers) long and drains an area of about 18,000 square miles (46,600 kilometers). It drops 68 feet (21 meters) at Cumberland Falls, now part of a state park in southern Kentucky. Below the falls, the river is dammed by Wolf Creek Dam. The river is navigable from the dam to the Ohio, a distance of about 460 miles (740 kilometers). The main cities on the Cumberland are Nashville and Clarksville, Tennessee. The Big South Fork National River and Recreation Area lies along the river’s South Fork.