South Dakota State Historical Society South Dakota State Historical Society The South Dakota State Historical Society is South Dakota's official state historical society and is located in Pierre, South Dakota at 900 Governors Drive. It is a part of the Department of Education The South Dakota State Historical Society was founded in 1862 as the Old Settlers Association of Dakota Territory. In 1901, the South Dakota Legislature established the Association as the official state historical society. In 1975, the State Archives were incorporated into the Society, which continues to operate them and also functions as a public library. In 1989 the Culture Heritage Center was
South Dakota Highway 21 was completely concurrent with US 81, which was also established at this time. This concurrency extended from the Nebraska state line to the North Dakota state line. By 1935, all of SD 21 was decommissioned except for its current alignment. South Dakota Highway 21 South Dakota Highway 21 (SD 21) is a state highway in the eastern part of the U.S. state of South Dakota. It connects Lake Norden and Hayti, completely within the south-central part of Hamlin County. SD 21 originally extended from the Nebraska state line to the North Dakota state line, completely concurrent with U.S. Route 81