The Dells of the Wisconsin River, also called the Wisconsin Dells, meaning “valley”, is a 5-mile (8-km) gorge on the Wisconsin River in south-central Wisconsin, United States. It is noted for its scenery, in particular for its Cambrian sandstone rock formations and tributary canyons. The formations are divided into the "Upper Dells" and the "Lower Dells" by the Kilbourn Dam.