The Cheyenne Mountain Complex is a hollowed out mountain in Colorado Springs that keeps track of everything in outer space and all planes in the North American airspace. Yes, this is the home of NORAD. Monolithic backlit screens provide a constant stream of information, including the 24/7 whereabouts of the President and Vice President.
In the event of a nuclear war, 800 personnel could survive in the Cheyenne Mountain Complex for 30 days completely cut off from the outside world. Twenty five-ton blast doors and over 1,319 thousand pound springs remain anchored within 1,700 feet of granite.
The complex is also said to be home to captured alien technology, hidden away deep below the ground levels