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 45 South Dakota Highway 45 South Dakota Highway 45 is a state route that runs north to south across much of central South Dakota. The northern terminus is at the North Dakota border as a continuation of North Dakota Highway 3, and runs south to South Dakota Highway 44 at Platte. It is in length. SD 45 was established around 1927. The southern terminus was at the intersection of present-day SD 50 and County Road 49 (CR 49) and the northern terminus was at the intersection of SD 10 in Leola. By 1932, it was extended south along what was part