The Greenbrier Bunker, officially known as Project Greek Island, was a secret United States government continuity facility located beneath the Greenbrier resort in White Sulphur Springs, West Virginia. Built between 1958 and 1962 during the Cold War era, this underground bunker was designed to house and protect the entire United States Congress in the event of a nuclear attack. The facility remained operational for over thirty years as a classified government project, with resort staff unknowingly serving as support personnel while the bunker's true purpose was kept secret from the public and even from most of the hotel's employees.
The bunker featured extensive facilities including dormitories, a hospital, a power plant, and a communications center, all maintained in a constant state of readiness. It was constructed with reinforced concrete walls and equipped with air filtration systems capable of protecting occupants from nuclear fallout. The facility was decommissioned in 1992 after its existence was revealed by The Washington Post, ending one of the most significant and secretive Cold War-era military installations in the United States.