There is no harbour on Jan Mayen. There is no town, no permanent population, and for most of the year not much daylight either. There is a strip of black volcanic gravel about a kilometre and a half long, no instrument approach, and a 2,277-metre volcano that generates its own weather.

On 29 August, a Royal Air Force A400M Atlas landed on it carrying US Marines, Royal Marines and two armoured vehicles.

The UK Ministry of Defence confirmed the deployment on 6 September. It was called Operation Atlantic City, it ran from 26 August to 4 September, and it happened on a Norwegian island that sits directly across one of the most strategically loaded stretches of water in the world.

The Least Convenient Runway in NATO

Jan Mayen is 377 square kilometres of volcanic rock in the Norwegian Sea, 55 kilometres long, shaped like a barbell — two lumps joined by a 2.5-kilometre isthmus. It has no indigenous population. The people there are Norwegian military personnel and staff of the Norwegian Meteorological Institute: eighteen through the winter, up to around thirty-five in summer, rotating in April and October.

The island is administered by the County Governor of Nordland, roughly a thousand kilometres away on the Norwegian mainland.

Jan Mayensfield — ICAO code ENJA — began life as a section of the island’s dirt road, widened in connection with a LORAN-C transmitter and completed in 1960. The first aircraft to land there was a Royal Norwegian Air Force Catalina flying boat on 17 September 1960. In normal years it sees perhaps eight flights, all of them C-130J Hercules of the RNoAF’s 335 Squadron out of Bodø.

The problem is Beerenberg. The mountain sheds a Kármán vortex street downwind — a train of alternating swirls that produces abrupt, unforecastable wind shifts across the strip. A Norwegian C-130 came close to crashing on takeoff there in 1991 for exactly that reason. There is no instrument approach, so an aircraft needs genuine visibility to get in, and turning back after a four-hour transit is a routine outcome rather than an embarrassment.

None of which is an accident of geography that NATO can ignore, because of where the island sits.

Why Anyone Cares About an Empty Island

The MoD’s own framing is unusually direct. Jan Mayen, it says, occupies a critical geostrategic position north of the Greenland-Iceland-UK gap — an area of water vital to the defence of northern Europe and the wider Euro-Atlantic area.

The GIUK gap is the chokepoint through which anything sailing from Russia’s Northern Fleet bases has to pass to reach the Atlantic. Jan Mayen sits north of it, in open ocean, with a runway. That combination is rare enough to be worth a great deal of effort.

Norway’s framing is blunter still, and about sovereignty rather than alliance solidarity.

What They Actually Did There

The MoD describes the exercise as integrating sensor and communications systems and practising maritime operations, surveillance, movement, survival and joint operations, against the obstacles of distance, extreme weather, limited infrastructure and rapidly changing conditions.

The US Marine Corps version is more specific and more revealing: integrating multinational sensors, command-and-control nodes and precision fires into what it calls a joint kill web, and validating expeditionary advanced base operations, combined fires, maritime domain awareness and sea denial.

Sea denial is the operative phrase. Naval News reported that the Kongsberg StrikeMaster — a twin Naval Strike Missile launcher mounted on a Bushmaster vehicle — was deployed to the island. That is a land-based anti-ship capability, delivered by air, to a rock in the middle of the Norwegian Sea. Note that this detail comes from a single outlet.

The operation name is not arbitrary. Atlantic City was the codename of a US wartime station at Nordlaguna on the island, established to support meteorological observation and Allied control of the North Atlantic. Troops visited the historic site on 29 and 30 August.

This was also not the A400M’s first visit. During the 2025 iteration, an RAF Atlas made what the MoD described as the first landing of its kind on Jan Mayen, delivering a single armoured vehicle from pre-positioned stocks in Norway. The 2026 sortie doubled that.

One unexpected side effect: the sortie showed up on Flightradar24’s coverage of an island that almost never generates any.

Arctic Sentry, and What It Signals

Operation Atlantic City sat inside Arctic Sentry, NATO’s enhanced Vigilance Activity for the Arctic and High North, launched in February 2026 and led by Joint Force Command Norfolk. It ran concurrently with Northern Viking 26 so the two could share maritime and sensing assets.

No participant has published a personnel figure, and it would be a mistake to assume the numbers were large. The point of an operation like this is not mass. It is proof that an alliance can put troops, vehicles and anti-ship missiles onto a runway with no fuel, no hangar, no radar approach and no way out except the way it came in — and take them home again.

For the aircrew involved, that is the interesting part. An A400M carrying thirty-seven tonnes into a gravel strip in the lee of an Arctic volcano is not a routine transport sortie. It is the sort of flying the aircraft was designed for and rarely gets asked to do.

Official footage of the RAF A400M delivering Marines and vehicles to Jan Mayen.

Sources: UK Ministry of Defence (GOV.UK), Forsvaret, US Marine Corps / DVIDS, NATO SHAPE, UK Defence Journal, Naval News, aeroTELEGRAPH, Forces News.