<Tr> <Th> GNIS feature ID </Th> <Td> 1265333 </Td> </Tr> <Tr> <Th> Website </Th> <Td> www.rcgov.org </Td> </Tr> <P> 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, on which the city is established, it is set against the eastern slope of the Black Hills mountain range . The population was 67,956 as of the 2010 Census . </P> <P> Known as the "Gateway to the Black Hills" and the "City of Presidents", it is split by a low mountain ridge that divides the western and eastern parts of the city . Ellsworth Air Force Base is located on the outskirts of the city . Camp Rapid, a part of the South Dakota Army National Guard, is located in the western part of the city . The historic "Old West" town of Deadwood is nearby . In the neighboring Black Hills are the popular tourist attractions of Mount Rushmore, the Crazy Horse Memorial, Custer State Park, and Wind Cave National Park . </P>

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