The US government seems to know far too much about its citizens, so it's disturbing to realize how little citizens know about the governing body. Learning what happens inside presidential bunkers and where the president would go during a nuclear attack is useful information, though. These bunkers were built in the middle of the 20th century, largely as a response to the mounting nuclear panic that accompanied the Cold War. Raven Rock, built in 1951, was one of the predominant shelters. From the underground city at the Raven Rock Mountain Complex in Pennsylvania, to the Greenbrier Bunker that's hidden in plain sight under a luxury resort in West Virginia, to the top-secret NORAD lair at Cheyenne Mountain in Colorado, these bunkers are incredibly secure.