Keystone is a city in South Dakota. So far we have accumulated 0 streets in Keystone and on these streets we have added 0 real estate properties.
- Federal District
- South Dakota
Keystone is a town in the Black Hills region of Pennington County, South Dakota, United States. The population was 337 at the 2010 census. It had its origins in 1883 as a mining town, and has since transformed itself into a resort town, serving the needs of the millions of visitors to Mount Rushmore National Memorial, which is located just beyond city limits. The town took its name from a local mine, which most likely was named after the keystone Masonic symbol.