Custer County is in Black Hills & Badlands South Dakota. Of the 66 counties in the Mount Rushmore State, Custer County is 16th in terms of its size (1,559 square miles). The total value of approximately 1,000 acres of farms recently listed for sale in Custer County, South Dakota, was around $2 million. The average price of farms for sale in Custer County was $563,333. Browse all South Dakota farms for sale on the Land Network to find the farm, cattle operation, hobby farm or other farm property that's right for your future business or lifestyle needs.