Hughes County, South Dakota Hughes County, South Dakota Hughes County is a county located in the U.S. state of South Dakota. As of the 2010 census, the population was 17,022, making it the least populous capital county in the nation, and the twelfth-most populous county in South Dakota. Its county seat is Pierre, the state capital. The county was created in 1873 and organized in 1880. It was named for Alexander Hughes, a legislator. Hughes County is part of the Pierre, SD Micropolitan Statistical Area. According to the U.S. Census Bureau, the county has a total area of , of which is land and
South Dakota Highway 65 the final segment stretching from US 16 in Kadoka to the Nebraska border south of Martin. Construction of a new road led to the connection of the two northern segments by 1932. The segment south of US 16 was re-designated as an extension of South Dakota Highway 63 in 1929. The route of SD 65 is defined in South Dakota Codified Laws § 31-4-174. South Dakota Highway 65 South Dakota Highway 65 (SD 65) is a state route in north-central region of the U.S. state of South Dakota. It begins at U.S. Highway 212 east of Dupree, then runs northerly