Hill City is the oldest existing city in Pennington County, South Dakota, United States. The population was 872 at the 2020 census. Hill City is located 26 miles southwest of Rapid City on U.S. Highway 16 and on U.S. Route 385 that connects Deadwood to Hot Springs. Hill City is known as the "Heart of the Hills", a distinction derived from its proximity to both the geographical center of the Black Hills, and the local tourist destinations.