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 22 by 1936, and included a north–south segment from Hazel to US 212. This north–south segment was decommissioned in the 1990s. South Dakota Highway 22 Spur (SD 22 Spur) was a spur route of SD 22 that extended from the mainline, at a point south of Gary, and traveled into that city. It was established between 1965 and 1971 and was redesignated as SD 101 in 1976. South Dakota Highway 22 South Dakota Highway 22 (SD 22) is a state highway in the east-central part of the U.S. state of South Dakota. It connects Hazel, Castlewood, and Clear Lake, within the