Keyhole Park is a 14,720 acre recreation area at the edge of the Black Hills National Forest, in Crook County. Until the Gold Rush of 1874, this region was land of the Sioux. Now, mariposas, sage brush, antelope and other flora and fauna dot the land.

The park includes five primitive campgrounds. Backcountry camping is allowed in this gorgeous country. Fishing for northern pike and walleye is a favorite pastime. Bike touring is possible with the paved road traveling around the reservoir. A two-mile trail allows mountain biking, as well as other park locations. In the winter season, the park serves as a location for cross-country skiing and snowshoeing.