what region of the united states is south dakota in
South Dakota South Dakota (/- dəˈkoʊtə/ ( listen)) is a U.S. state in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux Native American tribes, who compose a large portion of the population and historically dominated the territory. South Dakota is the seventeenth largest by area, but the fifth smallest by population and the 5th least densely populated of the 50 United States. As the southern part of the former Dakota Territory, South Dakota became a state on November 2, 1889, simultaneously with North Dakota. Pierre is the state capital and Sioux Falls, with a population of about 183,200, is South Dakota's largest city.
Interstate 90 in South Dakota Since April 2015 the speed limit is 80 miles per hour (130 km/h), except it is 65 miles per hour (105 km/h) between I-229 and Marion Road in Sioux Falls; or through Rapid City. The speed limit remains 75 miles per hour (121 km/h) between Rapid City and the Wyoming state line.