Three locations in the United States were used as landing sites for the Space Shuttle system. Each site included runways of sufficient length to provide adequate distance for the slowing-down of a returning spacecraft. The prime landing site was the Shuttle Landing Facility at the Kennedy Space Center in Florida, a purpose-built landing strip. Landings also occurred at Edwards Air Force Base in California, and one took place at White Sands Space Harbor in New Mexico. No space shuttle landed on a dry lakebed runway after 1991.