South Dakota spending, because of the proximity of many tourist attractions in the Black Hills and Ellsworth Air Force Base. The next eight largest cities in the state, in order of descending 2010 population, are Aberdeen (26,091), Brookings (22,056), Watertown (21,482), Mitchell (15,254), Yankton (14,454), Pierre (13,646), Huron (12,592), and Vermillion (10,571). Pierre is the state capital, and Brookings and Vermillion are the locations of the state's two largest universities (South Dakota State University and University of South Dakota, respectively). With a population of about 14,000, Pierre is the second smallest state capital in the United States. Of the ten largest cities
South Dakota Highway 391 South Dakota Highway 391 South Dakota Highway 391 (SD 391) is a state highway in the southwestern part of the U.S. state of South Dakota. It travels from Nebraska Highway 27 (N-27) at the Nebraska state line, southeast of Denby, to U.S. Route 18 (US 18) east-southeast of Denby. The highway is located entirely within Oglala Lakota County and in the Pine Ridge Indian Reservation. It is maintained by the South Dakota Department of Transportation (SDDOT), and is not part of the National Highway System. SD 391 begins at the Nebraska state line as a continuation of N-27 and travels