In 2017, researchers went looking for a city that had no surface.

Camp Century had been abandoned for fifty years. Snow had buried every entrance. The long trenches, barracks, laboratories, machine rooms and other structures that once made the place look surprisingly domestic in Army photographs were somewhere below an empty-looking section of the Greenland Ice Sheet.

The survey team had the old plans.

They also had radar.

Those two things did not quite line up.

When the Geological Survey of Denmark and Greenland compared its ice-penetrating radar measurements with the Army’s map, the buried installation appeared to have moved about 232 meters toward the west-southwest since the summer of 1959.

The ice had carried it away.

That is an odd fate for a military base.

Buildings ordinarily stay attached to geography. Camp Century was built inside geography that flowed.

The Army knew ice moved, of course. Its engineers measured the movement, studied snow compaction and watched the camp’s tunnels deform while people were still living inside them.

The engineering record shows that the ice was never a passive setting. It served as construction material and overburden, deformed around the tunnels while the camp was occupied, and later carried the abandoned site westward with the ice sheet.

Cutting a city into snow

Construction began in June 1959, roughly 200 kilometers inland from the ice-sheet margin in northwestern Greenland. The Army Corps of Engineers used what was essentially a cut-and-cover method: excavate deep trenches in compacted snow and firn, place corrugated steel arches over them, then cover the structures again with snow. By October 1960 the system could accommodate as many as 200 people in heated buildings beneath the surface.

The photographs make the project look almost reasonable.

A tracked snow machine cuts a trench.

Cranes lower steel arches.

Buildings go beneath them.

Snow goes back on top.

Once you accept the first strange proposition—that people should build a town inside an ice sheet—the remaining work begins looking disconcertingly similar to ordinary construction.

The Army’s 1965 technical report was remarkably optimistic about what had been achieved. It concluded that subsurface ice-cap camps were both feasible and practicable and that the experience gathered at Camp Century would be valuable in designing more of them.

The report’s optimism reflected a real operational achievement. Camp Century housed personnel year-round, supported laboratories and recreation spaces, and maintained vehicles, electrical systems and ventilation beneath the ice.

Life could continue while storms passed over a surface the occupants could barely see.

But the roof was never only a roof.

It was accumulating weight.

The walls began coming inward

Snow changes after it falls.

Layers compact. Snow becomes firn and eventually ice. Under pressure, ice deforms.

At Camp Century, tunnel deformation was measured at roughly 0.1 to 1 meter per year, depending on location and conditions. The engineering problem was not that the ice suddenly shifted like an earthquake. It was that structures intended to remain open were being very slowly squeezed by the material surrounding them.

The photographs from 1964 are particularly good evidence.

Steel arches that had begun with a clean semicircular profile no longer have one. The roof pushes down. Sidewalls come inward. Clearance disappears.

The Army had already encountered deformation while installing the reactor. Its own 1961 construction report notes that openings cut through steel arch sections could accelerate distortion badly enough that engineers redesigned exhaust structures to avoid weakening too much of the tunnel roof.

This was not a hidden defect discovered after abandonment.

People inside the base watched the ice pressing on their work.

They trimmed it.

They adjusted structures.

They measured it.

And, for a while, they lived with it.

A reactor in the trench

Camp Century’s most conspicuous technological experiment was PM-2A.

The portable nuclear power plant had been designed for assembly in an extremely remote place where bringing conventional fuel was expensive and difficult. The Army’s final 1961 construction report covers the reactor almost as a logistical exercise: design the components so they can be transported, move them across the ice, lower them into the camp and assemble a working nuclear plant beneath Greenland.

It worked.

PM-2A became the camp’s principal power source. Camp Century was occupied year-round from 1961 into 1963 using nuclear-generated electricity and heat. The reactor was later shut down, dismantled and removed; the Corps states that PM-2A was a temporary installation and was taken out after roughly three years.

That distinction is important because “abandoned nuclear base under Greenland” can easily become “the Army left a nuclear reactor under the ice.”

It did not.

The reactor came out.

Other things did not.

Camp Century’s PM-2A belonged to the same Army Nuclear Power Program as The Rod Was Supposed to Move Four Inches, the SL-1 investigation. The two reactors entered service within weeks of each other in 1961, but their histories diverged sharply: SL-1 became the site of the United States’ only fatal reactor accident, while PM-2A demonstrated that a prefabricated reactor could be transported to Greenland and assembled beneath the ice.

The railroad that did not go anywhere yet

Camp Century itself was never simply a fake scientific base.

That shorthand is another place the story gets mangled.

The scientific and engineering work was real. The Army genuinely wanted to know whether large installations could be built, supplied and maintained on the Greenland Ice Sheet. It also wanted to know whether vehicles and rail systems could move through subsurface corridors.

Those questions had a classified application.

In 1962, after an experimental railway had been tested at Camp Century, the Army proposed Project Iceworm to the Joint Chiefs of Staff: an enormous network of subsurface rail lines covering roughly 130,000 square kilometers of the ice sheet and capable of supporting as many as 600 ballistic missiles. The missiles would move through the network rather than remain permanently fixed at easily targeted launch sites.

The plan never became an operational weapon system. Project Iceworm was rejected in 1963.

It is tempting to say the moving ice killed it.

The evidence is not quite that obliging.

Engineering problems were real, especially the continuing distortion of tunnels. But later scholarship points to a combination of difficulties around the missile concept, changing strategic alternatives, geotechnical reality and political constraints rather than one clean moment when an engineer measured a bent tunnel and canceled the Cold War beneath Greenland.

The public camp and the secret proposal should therefore remain separate.

Camp Century existed.

Project Iceworm remained a proposal.

The difference is several thousand kilometers of tunnels and six hundred missiles.

The experiment that outlived the Army

The military installation did produce something with a much longer life than its engineers expected.

They drilled down.

Ice-core work at Camp Century began in the early 1960s. The first drilling systems were troublesome. Meltwater had to be controlled. Holes were deepened in stages, using different equipment and fluids as the project became more ambitious.

In 1965 an electromechanical drill pushed the principal borehole past 1,000 meters.

In July 1966 the drill reached the bottom of the Greenland Ice Sheet, about 1,387 meters below the surface, and continued into frozen material underneath. It was the first continuous ice-core drilling operation to reach the bed of an inland polar ice sheet and the first to recover a substantial core of the material beneath one.

The soldiers and scientists had reached past the climate record in the ice and into Greenland itself.

The deepest material was not glamorous.

Frozen sand.

Pebbles.

Rocks.

Silty ice.

The original drill log even contains conflicting depth entries and arithmetic mistakes. Modern researchers have been unusually candid that it is impossible to reconstruct every centimeter of the original recovery with certainty.

That messiness did not make the material less important.

Quite the opposite.

Someone kept the dirt

Most of the world’s famous ice-core story is about the ice.

Layers of snowfall trap chemical evidence and isotopic signals that allow scientists to reconstruct past atmospheres and temperatures. Camp Century helped establish that work; systematic isotope analysis of its core contributed to a roughly 100,000-year paleoclimate record published in 1969.

The frozen sediment underneath was much easier to neglect.

It moved through storage facilities. Pieces were cut. Two segments disappeared. Two were thawed. Much of what remained stayed frozen for decades.

Then scientists began looking at it again.

A 2021 study found preserved plant material and biomolecules in the sediment recovered beneath nearly 1.4 kilometers of ice. The evidence indicated that northwestern Greenland had experienced at least two episodes of ice-free, vegetated conditions during the Pleistocene and that the Greenland Ice Sheet had melted back substantially and re-formed at least once within roughly the past 1.1 million years.

That finding has direct importance for understanding how sensitive Greenland can be to prolonged warming.

It came out of dirt the Army pulled from beneath a military base.

The significance is direct: material recovered during a military engineering project later became evidence for Greenland’s deep climate history.

The city closes

Camp Century did not suddenly collapse one afternoon.

That would have made a cleaner ending.

The base stopped being occupied year-round after 1963 and continued seasonally for several years. The PM-2A reactor was removed in 1964. Camp Century was finally abandoned in 1967. Faster-than-expected tunnel deformation was likely one contributor to that decision, although the end of the larger Iceworm concept and changing military purposes belonged to the same history.

Much of the remaining infrastructure stayed where it was.

The prevailing engineering assumption was that continuing snowfall would bury and preserve what remained. A later climate study summarized the original expectation with an almost perfect phrase: the abandoned base would be entombed under perpetual accumulation.

That seemed reasonable enough at the time.

This was Greenland.

The base was already getting deeper.

Nobody needed the tunnels anymore.

Let the snow have them.

The waste story became too simple too

In 2016, Camp Century returned to the news for a very different reason.

A peer-reviewed study examined what climate warming might eventually do to the abandoned site. Under the high-emissions climate modeling then used, the authors found it plausible that the area could transition from accumulating more snow than it lost to losing more than it gained within roughly seventy-five years. If that happened and persisted, buried infrastructure and contaminants could eventually begin moving toward renewed interaction with the surface environment.

The headline version became considerably cleaner:

Climate change will expose a secret radioactive base by 2090.

That is not what the best current modeling says.

In 2021, GEUS researchers revisited the problem using local meteorological observations to correct biases in the earlier climate forcing and modeled several emissions pathways. Their result went the other direction for this century. The upper edge of the debris field, measured at about 32 meters deep in 2017, was projected to continue becoming more deeply buried, reaching roughly 58 to 64 meters below the surface by 2100. Maximum meltwater penetration in the simulations was only about 1.1 meters. The authors therefore judged interaction between surface meltwater and the buried debris extremely unlikely before 2100 under all scenarios they tested.

That does not convert Camp Century into an environmental nonissue forever.

The model ends in 2100. Its authors explicitly discuss assumptions and uncertainty in how firn handles meltwater. Greenland is warming, and the thermal state of the snow at Camp Century is changing.

But the correction matters.

The newer modeling materially changes the near-term risk picture: through 2100, the site is projected to become more deeply buried rather than exposed.

At least through the end of the modeled century, Camp Century appears likely to become deeper, not emerge.

What radar found

That is one reason the 2017 survey mattered.

Researchers drove an 80-kilometer radar grid over the old site and found the buried tunnel network remarkably legible. Most detected material lay deeper than 32 meters; the tunnel system itself appeared around 45 to 55 meters beneath the contemporary surface. The debris field occupied an area with a radius of less than a kilometer.

Some of the most peculiar features were not tunnels.

They were depressions in the internal layers of snow and firn.

Those downwarped layers corresponded to old liquid sumps that had collapsed as the ice compressed around them. Radar analysis suggested liquid hydrocarbons could still be present in one. GEUS also identified depressions associated with storage of water, sewage, glycol and what Army records called hot waste—water associated with the reactor system.

The reactor was gone.

The footprint of using it remained.

And then the researchers compared the radar with the old map.

The entire buried site had moved about 232 meters.

Three and two-thirds meters every year

That movement has not stopped.

A later peer-reviewed synthesis of six decades of measurements puts present horizontal ice flow at Camp Century at about 3.65 ± 0.13 meters per year, heading generally toward the west-southwest. Researchers found no significant long-term change in that rate over the modern measurement period.

The local surface has also thickened slightly since the 1990s—about 1.1 centimeters per year in the satellite and airborne altimetry record analyzed by the same team.

Those two measurements can coexist because an ice sheet is not a floor.

Snow accumulates vertically.

Ice compacts.

The whole mass moves horizontally.

The buried camp participates in all of it.

Camp Century is descending relative to newly fallen snow while also traveling across Greenland with the ice.

There is no ruin sitting underneath a fixed coordinate.

There is a moving debris field.

NASA flew over it by accident

In April 2024, NASA researchers were testing a different kind of airborne radar over Greenland.

They were interested in the ice itself—internal layers and the bed more than a kilometer below.

Camp Century appeared in the data unexpectedly.

The event was sometimes reported as NASA “discovering” or “finding” the lost base.

NASA says something much narrower. Earlier radar surveys had already detected and mapped Camp Century. The new UAVSAR instrument produced a more dimensional image in which individual structural elements could be distinguished in a way they had not been before. The scientific usefulness of that particular accidental image was, NASA noted, still uncertain.

That correction is worth keeping because the real story is better.

Nobody lost Camp Century.

Scientists knew approximately where it was.

Then they kept inventing better ways to look through the ice.

The 2024 image shows parallel features aligning with the old tunnel layout beneath a surface on which there is now almost nothing to see.

The city is there.

Collapsed, distorted, deeper than before and farther west.

The old plan

The Army’s 1965 layout drawing is tidy.

Long straight corridors.

Buildings aligned inside them.

A reactor area.

Laboratories.

Barracks.

A drilling trench.

Everything has a number and a place.

The map is an artifact from a moment when engineers believed the interesting question was whether people could establish permanent infrastructure inside an ice sheet.

They answered part of it.

Yes, for a while.

The less convenient answer came later.

The ice sheet did not become the ground simply because someone put buildings in it.

It kept behaving like ice.

It pushed the tunnels inward while people occupied them. It buried what they abandoned. It preserved a drill core that transformed paleoclimate science. It carried the remains of the base hundreds of meters away from the coordinates where construction started. And nearly sixty-five years later, radar can still match those remains to the Army’s drawing.

The old map still works.

You just have to move it 232 meters.

Sources & Further Reading

• U.S. Army Cold Regions Research and Engineering Laboratory, Camp Century: Evolution of Concept and History of Design, Construction, and Performance (1965). Principal Army engineering history of construction methods, structural performance and the contemporary conclusion that subsurface ice-sheet installations were feasible.
• U.S. Army Office of the Chief of Engineers, Construction of the Army Nuclear Power Plant PM-2A at Camp Century, Greenland (1961). Primary documentation of the reactor’s design, transport, assembly and operation beneath the ice.
• Karlsson et al., “Ice-penetrating radar survey of the subsurface debris field at Camp Century, Greenland” (2019). Key modern survey locating the buried tunnels, collapsed sumps and debris field and establishing displacement with ice flow.
• Colgan et al., “Sixty years of ice form and flow at Camp Century, Greenland” (2023). Current synthesis of the camp’s movement, including measured horizontal flow rate and local thickening.
• Vandecrux et al., “Firn Evolution at Camp Century, Greenland: 1966–2100” (2021). Essential for correcting the oversimplified claim that warming is expected to expose the abandoned base this century.
• Rittenour et al., “Scientific history, sampling approach, and physical characterization of the Camp Century subglacial material” (2024). Detailed scholarly reconstruction of the drilling program and surviving material.
• Christ et al., PNAS (2021). Major study showing that basal material recovered by the Army preserved fossil evidence of earlier ice-free Greenland environments.
• NASA Earth Observatory, “New View of the ‘City Under the Ice’” (2024). Authoritative account of the accidental UAVSAR image and NASA’s clarification that earlier radar had already detected the base.