Titan Missile Museum, Tucson, Arizona

Unknown Fields (UF) is a design studio, originating in London's Architectural Association, that "ventures out on annual expeditions to the ends of the earth exploring unreal and forgotten landscapes, alien terrains and obsolete ecologies." Mark Pilkington, author of Mirage Men and publisher of Strange Attractor, has just led this busload of architects, writers, filmmakers and artists in an exploration of the mythic landscape of the American Southwest, and the stories that it has inspired. Their trajectory took them from Kirtland Air Force Base in Albuquerque New Mexico to Black Rock City, Nevada, via sites of military, architectural and folkloric significance. Mark sent us occasional postcards from the edge. – David Pescovitz

The Titan Missile Museum, Tucson, Arizona

Fifteen miles south of Tucson, 140 feet underground, stands a monumental testament to the apocalyptic technology of the Cold War. Between 1963 and 1982 this was Titan II ICBM Site 571-7, one of 54 such silos operated by USAF Strategic Air Command at three locations around the country. The other two were in Little Rock, Arkansas and Wichita, Kansas, though 571-7 is the only site with all its components still in place.

One-hundred-and-three feet high and 10 feet in diameter, the Titan II had a range of 6500 miles and reached its target approximately 30 minutes after lift off. Each rocket – and there were 18 situated at each site – packed a 9 megatonne charge (almost twice the total explosive force unleashed by all sides in World War II) capable of devastating around 900 square miles in a single blast; a turn of a key selected whether the detonation took place on the ground or in the air.

Four staff lived in the bunker at any one time; initially these were all men, but towards the end of its operational life women also worked on the site. Most of their time was spent performing routine maintenance checks, but if the call to arms was heard, as it was, briefly, immediately after President Kennedy's assassination, two of them were expected to simultaneously turn the keys that would launch their silo's missile and erase the future. The missile's actual target was unknown to its caretakers, and remains classified to this day, though it would probably have been military and was certainly in the Soviet Union. Should one of the crew have suffered a crisis of conscience and refused to start World War III he or she would be shot and replaced by someone else – the crew were expendable, the missile, and its purpose, were not.

The missile launched 58 seconds after the keys were turned, leaving the crew with nothing to do but sit tight and await further orders; they might make use of the designated smoking area in a cramped corner of the control room, or listen to music on the 8-track stereo that once sat here. But what if further orders never arrived? The bunker held enough air and supplies to last 30 days, after which the choice of whether to venture outside or end the wait with a bullet was up to the team. If, as was likely, the Russians had Titans of their own, then the crew needn't have worried about what to do after the launch: the silo, a probable target, could only withstand a one megatonne strike at a distance of about half a mile. 

Accidents, unfortunately, did happen: in 1965 a fire killed 53 people at a silo in Searcy, Arkansas; this became known as the 'ghost silo' and gained a reputation for being haunted. Also in Arkansas, in 1980, a worker dropped a tool which struck a missile, causing a fuel leak and a subsequent explosion that killed one crew member and blew a 760 tonne blast door several hundred feet; the nuclear warhead was thrown clear of the site and mercifully didn't detonate.

Since the early 1990s the Tucson site has been run by the non-profit Arizona Aerospace Foundation and its thrilling tours are lead by a team of knowledgeable and enthusiastic volunteers. If you have time, ask for the deep access tour, though this can take over four hours to complete. Among the many highlights, look out for Richard DeSpain's beautiful drawings of the site in the debriefing room.