Retired top-secret installations are nothing short of jaw-dropping, and this one definitely does not fail to impress. This top secret facility was also once known as Titan II ICBM Site 571-7 because of the massive Titan II missile that it housed inside of it.
Located about 15 miles south of Tucson, this large 8 level installation is now a museum. During the time of its operation it was one of the most important missile sites.
During the 1963 President Kennedy assassination, this facility was put on full alert. The keys used to launch the missile were ordered to be placed on the tables at the launch consoles to prepare for a possible launch.
The Pentagon did not yet know if the Soviet Union has committed an act of war. Luckily the keys were never placed into their switches during this time. If the launch was ordered, National Command Authority would have specified a location out of the three per-programmed targets which, for security reasons (to avoid any human emotion), were not known to the crew.