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, USA. 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.

The Wisconsin River is a tributary of the Mississippi River in the U.S. state of Wisconsin. At approximately 430 miles long, it is the state's longest river. The river's name was first recorded in 1673 by Jacques Marquette as "Meskousing", which is rooted in the Algonquian languages used by the area's Native American tribes. The river's original meaning is obscure, but French explorers who followed in the wake of Marquette later modified the name to "Ouisconsin", and so it appears on Guillaume de L'Isle's map. This was simplified to "Wisconsin" in the early 19th century, before being applied to Wisconsin Territory and finally the state of Wisconsin.