As the Cold War fades into history, relics from the time go from top secret to public exhibits. Case in point is the Titan Missile Museum about 25 mi (40 km) south of Tucson, Arizona. Previously the US Air Force Facility Missile Site 8 or Titan II ICBM Site 571-7, the underground facility that was once home to a globe-spanning suborbital missile topped with a nine-megaton nuclear warhead is now a national landmark and a museum dedicated to the dark days of mutually assured destruction.

The Titan Missile Museum is the last of 54 Titan sites operated by the US Air Force from 1963 to 1987 as a hardened second-strike deterrent against Soviet nuclear attacks during the Cold War. The facility consisted of two underground, specially hardened buildings that acted as command center and support, as well as the silo that contained the liquid-fueled 103-foot (31-m) Titan II missile topped by a massive concrete and steel sliding lid.

In the event of an attack, two armed officers in the command center would wait for coded messages from the President of the United States. If one of these was received and verified, the GO code would be entered into the fire control system to arm the W53 hydrogen warhead and a pair of keys would be turned simultaneously for five seconds to launch the missile and send it toward its pre-programmed target.

Today, it is the only remaining Titan site, with the others either destroyed or converted into private residences. Even the museum has to conform to international arms control treaties. The warhead has been removed and the nose cone has an obvious hole in it to prove that it is empty, and similar holes have been cut in the propellant tanks and the heat shield. In addition, the protective top door is jammed in the halfway open position in a way that is clear to any satellite from orbit.

The above color illustration shows how the entire launch facility was buried underground for protection against a nuclear strike.

The Titan II was powered by a pair of hypergolic fuels, Aerozine 50 and nitrogen tetroxide, that ignite on contact.

The facility was protected by a series of large steel blast doors

If you want to experience this taste of Cold War times, the Titan Missile Museum is located at 1580 West Duval Mine Road, Sahuarita, Arizona. It's open 9:45 am to 5:00 pm Sunday to Friday (4:00 pm May to October) and 8:45 am to 5:00 pm on Saturday. It's closed Thanksgiving Day and Christmas Day. If you can't make it there, you can take a photographic tour via our gallery.

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