Colorado Springs is best known for its rugged outdoor attractions, but there’s much more to the place than national parks and nature reserves. Southwest of the city, for example, is Cheyenne Mountain and its three peaks, and they have guarded one of the world’s most sensitive secrets for more than half a century.
What the government concealed in Cheyenne Mountain would inspire untold speculative chatter, conspiracy theories and works of science fiction. But what was actually hidden there? Well, now we can see for ourselves.
The story began in 1961. Under the authority of the Army Corps of Engineers, the Utah Construction & Mining Company was commissioned to make inroads to the mountain and excavate massive tunnels in its slopes.
For the next three years contractors carved out a network of subterranean caverns large enough to house a small town. Sheltered beneath 2,000 feet of impenetrable granite, the tunnels crisscrossed a five-acre area.
Then, in the mid 1960s, the government began installing a complex of 15 three-story buildings. The cost of their construction? $66 million. The mysterious state-owned complex was nearly complete, but what was its function?
It was the height of the Cold War; east and west were locked into an escalating arms race and World War Three was potentially on the horizon. Both sides went to extraordinary lengths to enhance their military technology and to protect their civilians.
The facility is called the Cheyenne Mountain Complex, and it was designed to withstand a nuclear attack on American soil. For decades it was one of two homes to the North American Air Defense Command; a center for, among other things, defending against Soviet strikes.
The complex entered the public imagination after its fictitious depiction in the 1983 thriller War Games. In Terminator, meanwhile, it was shown as the base for Skynet. In TV series Stargate SG-1 it housed the interdimensional Stargate project.
The government did close the complex after the Cold War ended, but in 2015 the Pentagon announced that it would be reopened. Today, then, Cheyenne Mountain is undergoing a $700 million renovation ahead of its recommissioning as a military communications center.
The reason it’s needed? The enhanced threat from electromagnetic pulses (EMPs), which can disrupt and disable electrical devices, including military servers and sensors. EMPs, though, cannot penetrate Cheyenne Mountain’s solid granite fortifications.
The complex can be entered via two portals: north and south. They are linked by a single access tunnel running for two miles through the mountain. Visitors must walk through it for a mile before reaching the side roads that lead to the complex’s main chambers.
It’s much easier, of course, to drive. The Cheyenne Mountain Complex is vast enough to be serviced by several roads and parking lots; it’s effectively a super-secure underground world.
The buildings themselves were constructed using “battleship steel.” Over 1,000 springs and malleable pipes were fitted in their foundations to provide shock insulation against blasts or earthquakes. In the event of tremors the buildings shouldn’t move more than an inch.
Of course, it takes serious hardware to withstand the multi-megaton pressure of a nuclear explosion. Luckily, the steel blast doors at the entrance to the complex weigh a whopping 23 tons and can be closed within 40 seconds, even if their hydraulics fail.
The plug-shaped doors are operated via a system of hydraulic rods. In the event of a nuclear blast, when nothing could come in or out of the complex, the doors will automatically tighten against their seals.
Like something out of a Hollywood movie, the control center is furnished with a large conference desk and two screens. The one on the left shows the air-traffic situation nationwide; the one on the right details a close-up of Washington, D.C.’s Special Flight Restrictions Area.
The Cheyenne Mountain Complex naturally requires a significant amount of energy for its day-to-day operations. It’s powered, in fact, by six massive generators whose total collective output is 500 kilowatts – enough to electrify 5,000 homes.
Despite its many high-tech installations, however, the complex hides a few vestiges of the analog age, including a rather quaint-looking telephone affixed to a rock wall. The sticker on its case displays the emergency number “911.”
A network of underwater rivers and reservoirs supplies the complex with freshwater for drinking and cooling. The diesel that powers its generators, meanwhile, is stored in a subterranean lake.
The Cold War may be over, but the Cheyenne Mountain Complex continues to serve a vital defense role. If for any unfortunate reason the surface of the Earth becomes uninhabitable, for instance, it will be home to the last survivors of the human race.