Leaving Cheyenne Mountain

It took more than four years just to excavate and construct that mountain redoubt outside of Colorado Springs, that Cold War citadel whose two huge blast doors weighed 25 tons each. Within its confines, under 2,000 feet of Rocky Mountain granite, fifteen buildings were constructed, each mounted on steel springs, each spring weighing nearly half a ton, so that, when the Soviet nukes exploded, each building would sway but not collapse.