Rapid City, city in southwestern South Dakota. The seat of Pennington County, Rapid City got its name from its location on Rapid Creek, at the base of the Black Hills. It is the second largest city in South Dakota, after Sioux Falls. Rapid City is the center of a mining, ranching, grain-farming, and lumbering area. Manufactures include cement, wood products, electronic equipment, and processed food. Tourism is also important; the city is the gateway to Mount Rushmore National Memorial, the Black Hills, and other scenic attractions. The South Dakota School of Mines and Technology (1885) and a Sioux museum are located in the city, and Ellsworth Air Force Base is nearby. Rapid City was founded in 1876 after the discovery of gold in the Black Hills. It grew as a mining center and was incorporated as a city in 1882. In 1972 a flash flood of Rapid Creek swept through the city, killing more than 225 people. According to the 1990 census, whites constitute 88.2 percent of the city's population; Native Americans, 8.9 percent; blacks, 1.3 percent; and people of Asian origin, 1.0 percent. Hispanics, who may also be counted among other groups, represent 2.2 percent of the population. Population 46,492 (1980); 54,523 (1990); 57,513 (1998 estimate).
