Gregory County South Dakota (Vacant / Not In Use) has 4 places on the National Register of Historic Places including 1 place of National significance. Significant places include Fort Randall, Herrick Elevator, Herrick Public School, Pocahontas Schoolhouse.
Some of the country's most noteable architects helped create the Gregory County places including Caspary and Simons. Prominent architectural styles found in Gregory Country are Romanesque.