The Crystal River is a tributary of the Roaring Fork River, approximately 40 mi (64 km) long, in western Colorado in the United States. It drains a glacial valley, called the Coal Basin, south of Carbondale which was historically known as a center of coal mining in southwestern Colorado. It rises in northern Gunnison County in the Elk Mountains on the north side of Schofield Pass, passing through the ghost town of Crystal City, still inhabited by a few summer residents. It then flows north past Marble, then into Pitkin County past Redstone. It joins the Roaring Fork below Carbondale. State Highway 133 follows the river along much of its route north of Marble.