The Greenbrier's Secret Congressional Bunker

Beneath the Greenbrier resort in White Sulphur Springs, West Virginia lies a massive bunker code-named Project Greek Island, built in secret between 1958 and 1961 to house all 535 members of Congress in the event of a nuclear attack. The bunker has 153 rooms, a decontamination chamber, a power plant, a broadcast facility, and enough supplies to sustain Congress for 60 days. Its existence was kept classified for 30 years until Washington Post reporter Ted Gup exposed it in 1992. The government decommissioned it immediately after the story ran and it is now a tourist attraction.

Source: Wikipedia