An anonymous reader writes: From the 1950s to the 1970s Nike surface to air missiles were America's last line of defense against a potential attack by Soviet bombers. Over 200 Nike missile batteries guarded military installations and major urban areas. In case of an attack Nike Ajax and Nike Hercules missiles, some with nuclear warheads, would have been guided to their targets by ground-based analog electro-mechanical computers.
By the mid 1970s the Soviet Union's development of ICBMs (intercontinental ballistic missiles) had made the Nike missiles largely obsolete, and the missile sites were dismantled. The missiles and their launch equipment was scrapped and the buildings were abandoned. Today all that's left of most of the batteries is a few concrete slabs and some rusting bits of steel.
One Nike missile site, SF-88 near San Francisco has been restored to look close to the way it did when it was operational. The place has several Nike Hercules missiles and much of the associated launch equipment, complete with radar, analog guidance computer, and underground missile storage.