DECLASSIFIED documents have revealed the top secret behind a hidden “city” that was found buried deep beneath a vast sheet of ice.

A restricted military base from the Cold War era, Camp Century was created almost 100ft underneath a glacier in Greenland.

Nicknamed the “City Under the Ice,” Camp Century was a marvel of engineering for its time.

Built by the US Army Corps of Engineers, the base featured 21 interconnected tunnels spanning over 9,800 feet.

Officially, it was presented as a scientific research station.

But the true purpose of the military base remained a tightly held secret for decades.

Camp Century served as a cover for Project Iceworm – a covert plan to house a network of nuclear missiles in the ice, capable of striking the Soviet Union.

Plans were to put as many as 600 nuclear missiles, all aimed at blitzing the Soviet Union if things went south.

The camp was powered by an innovative portable nuclear reactor —the PM-2A — which supplied electricity and heat to sustain operations in the freezing Arctic conditions.

Despite its ambitious goals, the unstable ice proved to be a significant obstacle.

Over time, shifting and melting ice rendered Project Iceworm impractical, and the US abandoned the base in 1967.

The nuclear reactor was removed, but other materials, including hazardous waste, were left behind, eventually becoming entombed in the ice as the base was sealed off by nature.

However, a NASA scientist accidentally discovered the base once again during a routine research mission.

Chad Greene was snapping a stunning photo of the vast Greenland Ice Sheet when his plane’s radar detected the remnants of Camp Century.

“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 (JPL).

Initially, the team didn’t recognise what they had found.

But radar data then revealed individual structures within the base’s layout that corresponded to historical maps of the camp’s design.

Greene explained the unexpected nature of the find: “Our goal was to calibrate, validate, and understand the capabilities and limitations of UAVSAR for mapping the ice sheet’s internal layers and the ice-bed interface.”

Camp Century remains a time capsule of Cold War ambition, ingenuity, and secrecy.