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 52 until 1950, when U.S. Highway 18 was rerouted onto this road. In the early 1950s, there were two new, separate segments of SD 52. One was in the extreme southwest corner of the state. It began at U.S. 18 in Edgemont, and ran southerly to meet what is now South Dakota Highway 71 near Rumford. This road was renumbered as South Dakota Highway 471 in 1976. The second 1950's segment of SD 52 was the current alignment. South Dakota Highway 52 South Dakota Highway 52 (SD 52) is a state route that runs just north of the Missouri River, across