The Pima Air & Space Museum features a display of nearly 300 aircraft spread out over 80 acres (320,000 m²) on a campus occupying 127 acres (610,000 m²). Located in Tucson, Arizona, it is one of the world's largest, non-government funded aerospace museums. It is also home since 1991 to the Arizona Aviation Hall of Fame. The museum is adjacent to Davis-Monthan Air Force Base. The 309th Aerospace Maintenance and Regeneration Group (AMARG), affiliated with the base, also known as the "Graveyard of Planes" or "The Boneyard", is the largest aircraft storage and preservation facilities in the world. Bus tours of the boneyard leave from the museum several times a day from Monday to Friday.