“We were searching for an icy bed, but instead discovered ‘Camp Century,’ although at first we didn’t realize what we had found,” said Alex Gardner, a cryosphere specialist at NASA's Jet Propulsion Laboratory (JPL).
‘Camp Century,’ also known as the ‘City Beneath the Ice,’ was an Arctic military research base operated by the United States in Greenland from 1959 to 1967. It was located 240 kilometers east of Thule Air Base. The settlement comprised a series of tunnels stretching a total of three kilometers, with power supplied by a nuclear reactor.
After the base was abandoned in 1967, snow and ice covered the secret facility, which now lies at a depth of at least 30 meters.