NASA Radar Reveals Cold War ‘City Under the Ice’

A team flying over Greenland this past April spotted something unnatural in the vast ice sheet below: an abandoned city under the ice.

It sounds far-fetched, but the city is real and younger than you might think. It is Camp Century, a military base built out beneath Greenland by the U.S. Army Corps of Engineers in 1959. The team’s April 2024 flyby revealed Camp Century as an aberrational radar signal in an otherwise desolate swath of Greenland.

“We were looking for the bed of the ice and out pops Camp Century,” said Alex Gardner, a cryospheric scientist at NASA’s Jet Propulsion Laboratory and a member of the team, in an Earth Observatory release. “We didn’t know what it was at first.”

Camp Century was built in a frigid part of the world, where temperatures dip to -70° Fahrenheit (-57° Celsius) and wind speeds can exceed 120 miles per hour (193 kilometers per hour). Nevertheless, the engineering corps built a sprawling base that could host 200 soldiers at a time.

When Camp Century was built it was nearer to the surface, but the site was abandoned in 1967. In the intervening 57 years, at least 100 feet (30 meters) of snow and ice have accumulated on top of the site. The 47,000 gallons of radioactive waste produced by Camp Century’s nuclear reactor was buried along with it, according to the Atomic Heritage Foundation.

A tunnel in Camp Century in 1966. Photo: National Archives

Although abandoned for six decades, the work done at Camp Century continues to reveal details about Earth’s history. Soil cores recovered from the site are still analyzed today—with methods that didn’t exist when they were recovered—to help tell the story of Earth’s ancient climate. It’s easy to forget that millions of years ago, Greenland was a verdant landscape resplendent with mastodons, horseshoe crabs, piney forests, geese, and other critters. The cores recovered at Camp Century shed light on earlier conditions on Earth, helping scientists predict the climate in our planet’s future.

Though Camp Century was spotted in previous radar surveys, the April flyby used NASA’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) to image Greenland’s surface. The recent team was not looking for Camp Century on their northern sojourn; they were testing out the UAVSAR’s ability to map the internal layers of the ice sheet and the way the ice sheet meets the ice bed nearly a mile below the surface.

“In the new data, individual structures in the secret city are visible in a way that they’ve never been seen before,” said Chad Greene, also a cryospheric scientist at JPL, in the same release.

Lost cities are generally found in dense rainforest, where archaeologists make use of lidar imaging to see structures hidden underneath the dense foliage. Earlier this year, one such team found thousands of Maya buildings in Mexico’s Yucatán peninsula. The recent survey in Greenland made use of the same principle to find Camp Century, though it made use of radio waves to determine the location of the deserted site instead of laser light.

The new radar image (at the top of this article) do distort some aspects of the site’s layout. For one, the ice bed (represented as the thin green line running parallel to the ice’s surface) appears to be above Camp Century, even though it’s about a mile below it.

The UAVSAR test came off without a hitch, and contained an easter egg from the Cold War. Though there are concerns that melting of Greenland’s ice sheet could re-expose the camp and the various wastes within (including radioactive and biological), for now the image is a quirky reminder of our country’s military history.