The bunker is situated beneath The Greenbrier, a luxury four-star resort near White Sulphur Springs, West Virignia.
The high-class resort and hotel has attracted wealthy businessman, politicians and bankers since it was built in 1858.
During World War II, the hotel was briefly used as a detention centre for diplomats of enemy countries.
But rather than white sand dune golf bunkers, those checking in to the resort were unknowingly sitting next door to a post-apocalyptic nuclear protection facility ... Read even more