Your own island in the Baltic Sea: Is Flakfortet now available at a bargain price?

A good four nautical miles off Copenhagen, Flakfortet lies in the Sound like a strange, out-of-place feature: an island made up of around two million tonnes of rubble, concrete and sand, enclosed by a breakwater. A harbour lies sheltered behind this wall. Anyone mooring there is situated directly beneath the casemates of a former sea fort – with a view of Copenhagen on one side and the Swedish coast on the other.

For sailors, this is no ordinary stopover. Depending on the port of departure, the journey takes just 20 to 40 minutes. There are showers, a kiosk selling essentials, places to eat and historic bunker complexes to explore. The marina can accommodate up to 200 boats. It is precisely this combination of a sheltered harbour, an exposed location and a rich history that makes Flakfortet one of the most unusual destinations in the Øresund.

From a gun emplacement to a sailors’ haunt

The fort was built between 1910 and 1916 as part of Copenhagen’s coastal defences. Up to 550 soldiers were to be stationed here; however, the fort was never used in combat during the First World War. In 1968, the Danish military withdrew and the casemates fell into disrepair.

The second chapter in Flakfortet’s history began in 1975. The Copenhagen Sailing Union leased the abandoned complex. The gun emplacements were converted into moorings, and the officers’ mess into a restaurant. Since then, the island has become a meeting place for sailors, day-trippers and visitors from Copenhagen. In 2001, the Danish government sold the site to the Swedish company Malmökranen AB for three million kroner (around 401,000 euros). The new owners invested around two million euros sanitary facilities, a restaurant, a ferry service, drinking water treatment and a self-sufficient power supply.

Flakfortet is not exactly new to the market. A buyer was sought as far back as 2015, at which time the asking price was 56.5 million kroner (around 7.56 million euros) – without success. The next attempt to sell the property has been underway since January 2026. The current Advert by the estate agent now leads the rankings with 42 million kroner (around 5.62 million euros).

Bargain alert? It’s all in the small print

A price reduction of 32.75 million kroner (around 4.38 million euros) is striking. However, anyone simply dreaming of a private island with its own mooring should read the terms and conditions carefully. Flakfortet has been a listed building since 2002. Any alterations, extensions or major refurbishments must be agreed with the Danish Cultural Heritage Agency.

Even more importantly for sailors: public access is one of the conditions agreed upon during the state sale. Flakfortet must therefore not simply become a secluded private retreat. This was also a decisive factor in 2018, when the Danish museum authorities demanded that alterations be reversed to their 1995 state. The sanitary facilities would have been affected, and the harbour could not have continued to operate. Following significant protests from the sailing community and various associations, the authorities relented within a month. The then Controversy over the marina’s future shows just how closely the harbour’s future remains linked to heritage conservation.

The price is falling, but the responsibility remains

42 million kroner (around 5.62 million euros) for an island with a harbour, restaurants and Copenhagen on the doorstep is, at first glance, less off-putting than the original asking price. The current advertisement puts the ongoing owner’s expenses at 14,599 kroner per month (around 1,953 euros). However, it is not possible to deduce from this what maintenance, staffing, harbour operations and work required to preserve the listed building actually cost.

For an operator, a foundation or a very wealthy owner with a viable business plan, Flakfortet may well have become a more attractive prospect as a result. For most sailors, its significance lies elsewhere: as an unusual, publicly accessible harbour in the Øresund. And that is precisely what makes the sale so intriguing – not just who can buy the island, but who will keep it open to the sailing community in future.

Book recommendation

Cruising Guide: Denmark 2 takes you through the Danish archipelago, from South Funen via Zealand and Copenhagen to Bornholm. For a sailing trip in the Øresund, the guide provides local knowledge, navigation tips and harbour plans, thereby also helping readers to understand why Flakfortet is, for many crews, more than just a curious fortress island in the middle of the fairway.

Does the new price bring the dream of having our own marina a step closer – or does Flakfortet, precisely because of its history and public role, still belong to all sailors?