Approaching Rapid City via Interstate 90 from the east, you may notice traffic in addition to the RVs and motorcycles sharing the highway with you. Air Force jets soar overhead, flying into or out of Ellsworth Air Force Base, seven miles from Rapid City. Developed during World War II, Ellsworth has been an active base ever since. For visitors the South Dakota Air and Space Museum, immediately adjacent to the base, is free and home to an outdoor display of military aircraft. Planes range from a massive B-1B bomber to the B-25 that General Dwight Eisenhower used as his own transport during World War II. Indoor displays include artifacts from the 1935 Stratobowl manned-balloon flights, a joint mission of the Army and National Geographic Society. Launched from the Black Hills, two men in the balloon's gondola were the first to reach an altitude where they could see and photograph the earth's curvature.
