control center Located in Green Valley Arizona just south of Tucson is the only remaining preserved example of a Titan II missile silo. During the cold war there were 17 other similar silos around Tucson, as well as 18 in Wichita Kansas and 18 in Little Rock Arkansas. This Site (named 571-7) was on alert from 1963 to 1982 with a single 110 foot tall 330,000 pound titan II missile armed with a nuclear warhead. The missile compound is broken into three parts: The entryway which includes a stairwell, with a pair of blast doors leading to the "hardened" part of the site, the three-story command center, and the seven-level silo itself. The control center was a buried three-level, reinforced, concrete structure designed to withstand a nearby nuclear blast. The ground shock from a blast was absorbed by a three level shock isolation cage supported by eight shock mounts hung from the domed roof. Level 1 had sleeping quarters, a vestibule, a kitchen and dining area, a mechanical equipment room, and a latrine. Level 2 was connected to the cableway and personnel tunnel and also to the air intake shaft. This level had the controls for launching the missile and for monitoring the operations of the entire complex.
The missile silo was a reinforced concrete structure with inside dimensions of approximately 146 feet in depth and 55 feet in diameter. A launch duct, with an acoustical lining, was located in the center of the silo. Associated installed equipment, structures, and mechanisms included a survey transfer station, silo closure door, retractable work platforms, a collimator room, hazard sensing devices, and a small equipment and personnel elevator operating between levels 2 and 8. Two exhaust ducts carried missile exhaust and ingested air from the flame deflector, through cascade vanes, to the surface. In the mid-'80s as part of the Strategic Arms Limitations Treaty (SALT) with the then-Soviet Union, the other 53 Titan II sites were destroyed or filled with concrete to make innoperable. At the time of the SALT treaty theTitan II sites were already considered obsolete, and were being replaced by a more mobile and less infrastructure dependent launch system which was much cheaper to maintain.