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/sq mi (217.3/km). The racial makeup of the city was 84.33% White, 0.97% African American, 10.14% Native American, 1.00% 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.
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.
Rapid City is a major transportation hub for the Northern Plains. Rapid City Regional Airport provides flights to the airline hub cities of Denver, Minneapolis, Salt Lake City, Las Vegas, Phoenix/Mesa and Chicago. The airport also has extensive General Aviation operations, including wildfire fighting activities and medical flight support to Rapid City medical facilities and Indian Health Service operations in the Dakotas.
Historically Rapid City was served by 3 Railroads, today Rapid City is served by the Dakota Minnesota & Eastern, now owned by 15,000 mile long Canadian Pacific. The DM&E serves the Northern Black Hills and heads south into Nebraska. The DM&E's lines run east to Minnesota and south through Nebraska to connect with major transcontinental railroads (Burlington Northern Santa Fe and Union Pacific).
Rapid City's central location allows easy transport of products to both coasts, and trucking is a major business activity in the city. Improved connections with Denver and I-80 to the south, via the Heartland Expressway now under construction will primarily benefit local trucking.
Rapid City's location on the boundary of the Western and Eastern power grids, together with the hydroelectric plants of the Mainstem Dams on the Missouri River and the large coal fields and power plants of the Powder River Basin of Wyoming make it one of the points where the two national power grids connect with each other, allowing switching of electrical power from east to west and vice versa.