This is a National Natural Landmark that is a white sandstone remnant of Tertiay deposits that originated as a volcanic ash. Late Cretaceous, Paleocene, Oligocene, and Miocene strata are displayed as well.The formation resembles the Nation's Capitol Building in Washington, DC and is located on public land in the Long Pines land unit of the Custer Gallatin National Forest.
Short Walk: From Camp Crook, South Dakota, go 3 miles west on Highway 20. At fork, turn right on Forest Road 3116 (Capitol Rock Road) and follow the road approximately 7 miles to Capitol Rock. Capitol Rock may also be access from the west on Forest Service roads, but that route is a much longer, narrow gravel and dirt two track. The route from the west should only be used if familiar with the area or confident in navigation skills. Either route may be difficult in winter or after rain.
Family Friendly: Visible from the road or a short hike up to a unique formation.
Gem Type: Geologic Feature