This secret military facility, constructed on Danish territory, was named “Camp Century”.

YouTube commenter George McGovern explains:

Within three years after it was excavated, ice core samples taken by geologists working at Camp Century demonstrated that the glacier was moving faster than anticipated and would destroy the tunnels and planned launch stations in about two years. The facility was evacuated in 1965, and the nuclear generator removed. Project Iceworm was canceled, and Camp Century closed in 1966.


 YouTube commenter Mumbo Jumbo clarifies:

Camp Century was a cover story to hide from the Danish government “Project Iceworm” which was the code name for a top-secret United States Army program during the Cold War to build a network of mobile nuclear missile launch sites under the Greenland ice sheet.