Pennington County, South Dakota, USA

Pennington County occupies about 2,784 square miles in western South Dakota, extending from the forested Black Hills eastward across foothills, open prairie and portions of the Badlands. Rapid City, the county seat and largest community, anchors the populous western part of the county, while smaller municipalities include Box Elder, Hill City, Keystone, New Underwood, Wall, Wasta and Quinn. The county contains several nationally significant landscapes and attractions, including Mount Rushmore National Memorial, parts of Badlands National Park, Black Hills National Forest, Custer State Park’s northern approaches and the Minuteman Missile region, while Ellsworth Air Force Base lies near its eastern urban edge. Elevation and land cover vary sharply from rugged pine-covered mountains and reservoir valleys in the west to dry grasslands and eroded formations in the east. Pennington County was created in 1875, organized in 1877 and named for Dakota Territory Governor John L. Pennington; it had 109,222 residents in the 2020 census and is South Dakota’s second-most-populous county.