Under the code name “Project Iceworm,” the US military planned a secret missile base in the Greenland ice sheet. Denmark was not informed.
Jan 17, 2026, 8:46 p.mJan 17, 2026, 8:46 p.m
In April 2024, a team of NASA scientists flew over the gigantic ice sheet of Greenland. The aim of the reconnaissance flight was to test a new radar for mapping the Greenland ice cap. This suddenly discovered strange shapes in the ice. Only the use of a ground-penetrating radar brought clarity: the structures in the ice sheet belonged to a long-abandoned US base Camp Centurywhose remains are hidden under the ice.
Camp Century consists of 26 tunnels and caverns in the ice sheet, which are a total of three kilometers long. Today they lie under a layer of ice more than 30 meters thick. In 1958, when construction of the facility began, it was only eight meters. Camp Century was supposed to be just one of several locations in a much larger US military project: the highly classified one Project Icewormwhich aimed to station nuclear missiles in the Greenland ice sheet. And this, it should be noted, without the knowledge of the Danish government.
Camp Century’s tunnels were first cut into snow and ice as trenches and then covered over. Image: Getty Images
Gigantic missile base under the ice
As part of Project Iceworm, a system of subglacial launch pads for US nuclear missiles was to be built in the north of Greenland over an area of 130,000 square kilometers – three times the size of the mother country Denmark. In the planned branched tunnel system, the total length of which would have reached 4000 kilometers, 60 control centers (Launch Control CentersLCC) and 2,100 missile silos will be set up, operated by a total of 11,000 soldiers. Small semi-mobile nuclear reactors were supposed to supply them with electricity.
Around 600 Minuteman ICBMs were to be stored there, which could be transported back and forth on rails so that their exact location remained secret. These are specially adapted for use in the subglacial silos Iceman missiles would have only been two-stage and would have had a range of 5,500 kilometers – sufficient for most important targets in the Soviet Union.
Expansion of a tunnel from Camp Century. Image: Getty Images
The layer of ice over the launch silos would have already offered a certain level of protection against Soviet nuclear attacks. But the actual protection of the silos, each about 6.5 kilometers apart, would have been their invisibility under the ice cap. Upon completion of Project Iceworm, the Soviets estimated that they would have needed 3,500 eight-megaton warheads to destroy it in its entirety.
US interest in Greenland
The background to this mega-project was the Cold War, which began after the Second World War. Since the Soviet Union also became a nuclear power in 1949, the development of long-range supersonic bombers and intercontinental ballistic missiles has shaped the nuclear arms race between the superpowers. This meant that the remote northern polar region gained strategic importance, as the shortest flight connections between the centers of the USA and the Soviet Union ran through this area. Greenland, for example, is halfway between Moscow and Washington.
No wonder the US military established military bases in the region: Ladd Air Force Base in Alaska, Goose Air Force Base on Labrador in Canada and Thule Air Base in Greenland, the northernmost base of the US Air Force. Until the Second World War, the USA had little interest in the largest island in the world, but then, on April 9, 1941, the Danish ambassador to the USA, Henrik Kauffmann, and US Secretary of State Cordell Hull signed a defense contract. This was in 1951 as Defense of Greenland Agreement (Greenland Defense Agreement) was renewed, which allowed the USA to keep its military bases in Greenland and – within the framework of NATO – to establish new bases.
And this is what the USA did in the following years. In addition to the Thule Air Base, which is the only one still in operation today (although today it is called Pituffik Space Base), two more air force bases were built: Narsarsuaq and Special current. All three were intended as operational bases for strategic bombers and also served as gas stations.
Camp Century and US Air Force bases in Greenland.Map: Wikimedia/Watson
Swiss ice cutters for the US Army
Camp Century, created as a test site for Project Iceworm, was located on an enormous ice plain 150 miles from Thule Air Base. It was the closest suitable location to the Thule supply base and was not affected by the summer ice melt. Work began here in June 1959, and the logistical challenge was enormous: building materials and tools had to be brought in from Thule using a tracked vehicle. Such a journey took about 70 hours. Working in this bitterly cold icy wasteland was not easy – at night temperatures dropped to minus 50 degrees Celsius and the wind could blow ice and snow through the air at speeds of up to 200 kilometers per hour.
Using special ice cutters designed in Switzerland, the workers dug deep tunnels into the ice, which initially remained open at the top. They were then covered with curved steel plates, which were then covered with snow and ice.
When construction of Camp Century was completed in October 1960, the base provided the manning’s two hundred soldiers with dormitories, a kitchen, a hospital, a laundry, a cafeteria, a communications center, a recreation room, a chapel, and even a barbershop.
There were also offices, a radio station, storage rooms for materials and fuel, a laboratory and a backup diesel generator. But one was used to supply energy semi-mobile nuclear reactor (PM 2A) with two megawatts of power, which of course had to be treated carefully in the icy climate as the metal of its shell quickly became brittle.
Deceived Danes
Camp Century itself was not secret. Officially it was considered a research center in the polar region, and the US Army even made a film about it. In fact, scientists worked on Arctic research under the auspices of the Army Polar Research and Development Center. However, the camp’s function as a test site and prototype for Project Iceworm remained secret until 1997. The US Department of Defense explained to the Danish authorities in 1960 that the purpose of the camp was to test various construction techniques in Arctic conditions, study practical problems with a semi-mobile nuclear reactor and conduct scientific experiments on the ice sheet.
Drilling was also carried out at Camp Century to recover drill core.
It was clear to the Americans that there was a strong opposition on the Danish side to stationing nuclear weapons on their territory – at least officially. Things looked different behind closed doors: When the US ambassador to Denmark privately addressed Danish Prime Minister Hans Christian Svane Hansen in 1957 and asked whether Denmark would like to be informed if the US stationed nuclear weapons in Greenland, Hansen only replied after five dayshe considers the ambassador’s statements “not worth commenting on.”
The Americans understood this to mean that the Danish government did not want to know exactly what activities the USA was developing in the far north. This may be true, but even if the Danes were willing to overlook the secret storage of small stockpiles of nuclear weapons at Thule Air Base, they are unlikely to have consented to a massive American nuclear presence like Project Iceworm.
Problems and shutdown
But that didn’t happen, as we know. Massive problems soon became apparent: the Greenland ice was simply too unstable. The ice sheet moved faster than originally expected. For example, the ceiling of the room containing the Camp Century nuclear reactor began to sink and had to be raised by almost five feet. At such a rate of ice displacement, the entire complex would have been destroyed within two years. Storing nuclear missiles in such unstable tunnels did not seem advisable.
In addition, the technology of launching nuclear missiles from submarines made rapid progress in the early 1960s. A fleet of submarines that could fire Polaris missiles from the Arctic Ocean, the North Sea, the Mediterranean, or the western Pacific offered far more advantages than an expensive missile base under the ice of Greenland. The strategic submarines, which enable a nuclear second strike after an enemy first strike, made Project Iceworm and thus Camp Century obsolete.
Luke for entering a tunnel at Camp Century. Image: Getty Images
In 1963, the United States officially canceled the project and Camp Century was converted into a summer military base. The nuclear reactor was shut down in 1964 and replaced with diesel generators. Two years later, the US military finally abandoned the camp, which gradually sank under a thick layer of ice.
Toxic legacy
Also buried under the ice layer – in addition to the entire infrastructure – are the toxic waste that the military left behind. According to estimates, there are around a hundred football fields in an area 9200 tons of building materials200,000 liters of diesel and toxic pollutants such as Polychlorinated benzenes (PCB), 24 million liters of wastewater and slightly radioactive cooling water from the nuclear reactor.
In the 1960s, when “global warming” was still an unknown term, it was assumed that the contaminated sites would be preserved forever under the accumulating masses of snow and ice. In fact, when the camp was abandoned, the ice layer was about 12 meters thick; today it is around 35 meters thick. And for the time being, probably for a few decades, it will continue to grow.
After that, however, the melting will be greater than the snowfall, and layer after layer of ice will be removed again. This is the conclusion reached by the Canadian climate researcher William Colganwho and his team examined documents and plans to assess how deeply the toxic legacy is buried. In his study from 2016 he estimates that their exposure will be irreversible by 2090 – or even sooner if climate change accelerates.
At that point at the latest, the question will arise as to who is responsible for cleaning up – a question that is likely to cause tension between Denmark, Greenland and the USA. By then, however, Greenland could have long since become an independent state – or a US state, if so US President Donald Trump imposes his will can.
Video: Watson/Lucas Zollinger