Camp Century-aka "Project Iceworm"-was a "city under ice," according to the U.S. Army, a "nuclear-powered research center built by the Army Corps of Engineers under the icy surface of Greenland," as Frank J. Leskovitz more specifically explains.
A fully-functioning "underground city," Camp Century even had its own mobile nuclear reactor-an "Alco PM-2A"-that kept the whole thing lit up and running during the Cold War. According to Leskovitz, the Camp's construction crews "utilized a 'cut-and-cover' trenching technique" during the base's infraglacial construction:
Long ice trenches were created by Swiss made "Peter Plows," which were giant rotary snow milling machines. The machine's two operators could move up to 1200 cubic yards of snow per hour. The longest of the twenty-one trenches was known as "Main Street." It was over 1100 feet long and 26 feet wide and 28 feet high. The trenches were covered with arched corrugated steel roofs which were then buried with snow.
Prefab facilities were then added, with "wood work buildings and living quarters... erected in the resulting snow tunnels." Leskowitz continues:
Each seventy-six foot long electrically heated barrack contained a common area and five 156 square foot rooms. Several feet of airspace was maintained around each building to minimize melting. To further reduce heat build-up, fourteen inch diameter "air wells" were dug forty feet down into the tunnel floors to introduce cooler air. Nearly constant trimming of the tunnel walls and roofs was found to be necessary to combat snow deformation.
Somewhat incredibly, though, Camp Century went from scientific outpost to research-site for the U.S. Army's attempt to install battle-ready nuclear missiles underneath the Greenland ice sheet-the so-called "Project Iceworm" mentioned earlier. The following video, produced by the U.S. military, explores the site's strange technical circumstances as well as its complicated defensive history.
Indeed, "During this period of the Cold War," Leskovitz explains, "the US Army was working on plans to base newly designed 'Iceman' ICBM missiles in a massive network of tunnels dug into the Greenland icecap. The Iceworm plans were eventually deemed impractical and abandoned," and, "due to unanticipated movement of the glacial ice," the entire subterranean complex was eventually left in ruins.
The idea that the moving terrain of a glacial ice sheet could be considered a stable-enough launching point for nuclear missiles is astonishing, and the idea that the U.S. Army once ran a top secret, and rather Metallica-sounding, "city under ice" just shy of the North Pole only adds to the story's disarming surreality.
In any case, more photographs, including of the Army's mobile nuclear reactor, are available on Leskovitz's site.