Rapid City (Lakota: Mni Lúzahaŋ Otȟúŋwahe; “Swift Water City”) is the second most populous city in South Dakota and the county seat of Pennington County. Named after Rapid Creek, where the settlement developed, it is in the western part of the state, located on the eastern slope of the Black Hills mountain range. The population was 67,956 as of the 2010 Census.
Rapid City is located at 44°04′34″N 103°13′42″W / 44.076188°N 103.228299°W / 44.076188; -103.228299. The downtown elevation of Rapid City is 3,202 feet (976 m). Rapid City is located in the shadow of Black Elk Peak, which at 7,242 feet (2,207 m), is the highest point east of the Rocky Mountains.
According to the United States Census Bureau, the city has a total area of 55.49 square miles (143.71 km), of which 55.41 square miles (143.5 km) is land and 0.08 square mile (0.2 km) is water.
Rapid City is located on the eastern edge of the Black Hills, and has developed on each side of the Dakota Hogback. Rapid City’s “Westside” is located in the Red Valley between the foothills of the Black Hills proper and the Dakota Hogback, so named for the red Spearfish formation soils and the way the valley completely encircles the Black Hills. Rapid City has expanded into the foothills, with developments having been built on both ridges and in valleys developed, especially in the last 20 years. This arid edge area has a higher risk of wildfire, as shown by the Westberry Trails fire in 1988.
Skyline Drive follows the summits of the Dakota Hogback south from near Rapid Gap (where Rapid Creek cuts through the Hogback) to a large high plateau that forms the current south edge of Rapid City. The Central and Eastern portions of Rapid City lie in the wide valley of Rapid Creek outside the Hogback. It includes a number of mesas rising a hundred feet or more above the floodplain.
As of the census of 2010, there were 67,956 people, 28,586 households, and 16,957 families residing in the city. The population density was 1,226.4 inhabitants per square mile (473.5/km). There were 30,254 housing units at an average density of 546.0 per square mile (210.8/km). The racial makeup of the city was 80.4% White, 1.1% African American, 12.4% Native American, 1.0% Asian, 0.1% Pacific Islander, 0.7% from other races, and 4.1% from two or more races. Hispanic or Latino of any race were 4.1% of the population.
There were 28,586 households of which 29.9% had children under the age of 18 living with them, 41.2% were married couples living together, 13.1% had a female householder with no husband present, 5.1% had a male householder with no wife present, and 40.7% were non-families. 32.9% of all households were made up of individuals and 11.1% had someone living alone who was 65 years of age or older. The average household size was 2.29 and the average family size was 2.90.
The median age in the city was 35.6 years. 23.9% of residents were under the age of 18; 10.6% were between the ages of 18 and 24; 25.7% were from 25 to 44; 25% were from 45 to 64; and 14.5% were 65 years of age or older. The gender makeup of the city was 49.5% male and 50.5% female.
As of the census of 2000, there were 59,607 people, 23,969 households, and 15,220 families residing in the city. The population density was 1,336.7 people per square mile (516.1/km). There were 25,096 housing units at an average density of 562.8 per square mile (217.3/km). The racial makeup of the city was 84.33% White, 0.97% African American, 10.14% Native American, 1.0% Asian, 0.06% Pacific Islander, 0.73% from other races, and 2.77% from two or more races. Hispanic or Latino of any race were 2.77% of the population.
There were 23,969 households out of which 31.2% had children under the age of 18 living with them, 46.7% were married couples living together, 12.6% had a female householder with no husband present, and 36.5% were non-families. 29.4% of all households were made up of individuals and 10.0% had someone living alone who was 65 years of age or older. The average household size was 2.39 and the average family size was 2.96.
In the city, the population was spread out with 25.3% under the age of 18, 11.8% from 18 to 24, 28.7% from 25 to 44, 20.9% from 45 to 64, and 13.2% who were 65 years of age or older. The median age was 35 years. For every 100 females, there were 96.2 males. For every 100 females age 18 and over, there were 93.6 males.
As of 2000 the median income for a household in the city was $35,978, and the median income for a family was $44,818. Males had a median income of $30,985 versus $21,913 for females. The per capita income for the city was $19,445. About 9.4% of families and 12.7% of the population were below the poverty line, including 17.6% of those under age 18 and 6.9% of those age 65 or over.