10 Abandoned Sea Forts, Towers & Anti-Submarine Platforms

Abandoned sea forts off the coast of Britain (Image: via subterrain.org.uk; abandoned sea forts, towers and other defences)

There are few lonelier places on earth than a sea fort, especially those manned by only a handful of people at a time. Sea forts have long served as defensive positions, as lighthouses, and as early warning stations; while built, they’re out of necessity prime, peak examples of state-of-the-art engineering. As they age, though, they’re often more trouble than they’re worth to repair, and are left to the elements. This article highlights 10 abandoned and repurposed sea forts, anti-submarine towers and other offshore military platforms.

Solent Forts, England

solent-fort-no-mans-land (Image: Colin Babb, above: No Man’s Land sea fort)

The Solent Forts, also known as Palmerston’s Follies, were built in the late 1800s off the coast of Portsmouth as part of England’s maritime defence network. At the time of their conception, Louis Napoleon was coming to power and emerging not only as Emperor Napoleon III, but also taking the head of a powerful army. The British government, understandably concerned, commissioned the four forts as early defence.

solent-fort-st-helens (Image: Editor5807)

No Man’s Land, St. Helens (above), Spitbank and Horse-Sands were constructed, but were incredibly short-lived. When the seabed was found to be too unstable to safely support the fortifications, the construction of a fifth sea fort, Ryde Sand, was abandoned.

solent-fort-spitbank (Image: Sian Abrahams; Spitbank)

Over time, advances in steam power and other technologies made it difficult to keep the forts updated as a viable defence system. By the time they were completed, the original threat that they had been built to combat had passed. The defensive structures were used throughout World War Two mainly as signal and warning facilities, as they had not been built to accommodate the heavy artillery that a fully armed fort would require. The structures were also used for the seizure of French ships off the coast, but were ultimately decommissioned in 1956.

solent-fort-horse-sands (Image: Graham Horn; Horse-Sands fortification)

Recently, the abandoned sea forts have been given new life. The Horse-Sands Fort is being remodelled and restored to its original condition, with plans to open it as a museum. Spitbank is being converted into a luxury hotel, and No Man’s Land is getting a face-lift and being turned into a banquet facility, dining hall, spa and cabaret.

Maunsell Sea Forts, England

maunsell-forts-shivering-sands (Image: Hywel Williams)

Named for their designer, Guy Maunsell, the Maunsell Sea Forts were a crucial component of Britain’s defence network during World War Two. Seven forts – four naval and three army – were built in the Thames estuary, and several can still be seen on the horizon today – well known local landmarks to this day.

The Army sea forts were a series of seven towers, all connected by walkways to a central control tower. Building commenced in 1942 with the purpose of providing anti-aircraft defence, and the forts were armed with both gun and searchlight towers. Constructed on land and floated out to sea where they were installed, the now abandoned sea forts proved very successful, and plans were drafted to build more of the towers. Those plans were scrapped in 1952, however, although the Maunsell forts are still considered among the most successful early incarnations of today’s off-shore structures.

maunsell-forts-red-sands (Image: Russss; these abandoned sea forts look like something from a sci-fi movie)

Of the three Army forts – Shivering Sands (top), Red Sands (above) and Nore – only two remain standing after Nore collapsed following a 1953 storm that damaged the structure and compromised its integrity; the unfortunate Maunsell fort was later hit by a ship, and was ultimately dismantled after the deaths of four civilian caretakers.

maunsell-forts (Image: via subterrain.org.uk)

The naval forts had two main supports and anti-aircraft guns mounted on the top. Rough Sands, Sunk Head, Tongue Sands and Knock John were all decommissioned by the end of the 1940s, but had a brief – and rather weird – period of occupation after that. From 1965 to 1967, the abandoned sea forts were, perhaps appropriately, the home of pirate radio stations. The stations, which originally started in fishing boats, were headquartered on all four of the otherwise abandoned naval towers – after the Marine Broadcasting Act was passed, they were replaced by Radio 1 and Radio 2.

maunsell-forts-3 (Image: via subterrain.org.uk; abandoned Maunsell forts from below)

Knock John Maunsell fort is still in a good state of repair today. Its guns were only removed in 1992, and all ladders have now been removed from the fort, making it impossible to board – largely due to the idea that it might have been used for smuggling. Originally, there were 49 sea forts planned for construction on the River Thames, and another 38 on the Mersey.

Texas Towers, United States

texas-towers (Image: via Wikimapia; now defunct Texas Towers while operational)

Contrary to what their name implies, the Texas Towers were quite a distance from Texas. Built off the North Atlantic seaboard of the United States, they were given their name because of their resemblance to the oil rigs of the Gulf of Mexico. The towers, built in the late 1950s, were part of a defence network designed to detect incoming hostile forces during the Cold War. Five towers were originally planned, but only three were built – and one proved deadly.

Each of the distinctive, triangular structures cost about $21 million to build and required a crew of 50 men. Towers 2 and 3 (below) were off the coast of Nantucket and Boston, while the ill-fated Tower 4 was set 75 miles off the coast east of Barnegat Inlet, New Jersey.

texas-towers-2 (Image: US Air Force)

While 2 and 3 were anchored on relatively stable ground, Tower 4 (below) was plagued with problems from the start. Construction crews hadn’t been prepared for the deep, unstable mud that was at the location of the 4th tower. Built anyway, it was subjected to numerous repairs and attempts to stabilise the structure, which would constantly move with even everyday winds and waves.

texas-towers-3 (Image: NOAA)

Nicknamed Old Shaky by the crews who worked on it, they were also warned not to try to shave with a straight razor or bare blade, should a sudden gust of wind make the Texas tower shake and cause their hand to slip. In the winter of 1960, emergency repairs were launched to try to salvage the tower, but it collapsed on January 14, 1961. All 28 people aboard were killed. The other two towers didn’t fare much better, and were abandoned in the early 1960s after suffering a series of problems related to the wear and tear of the elements.

Fort Boyard, France

Abandoned Fort Boyard, France (Image: Fabien1309)

Fort Boyard isn’t technically abandoned anymore; it’s notable for having perhaps one of the most bizarre fates of a repurposed structure, as the setting of a television challenge show that has the same name. But that doesn’t make the history of the historic sea fort any less impressive.

fort-boynard-france-2 (Image: Mpkossen)

Located off the coast of France, the original plans for the fort were developed in the 17th century by Louis XIV. But the technology of the time wasn’t quite up to the required standards, and Fort Boyard wasn’t actually begun until another of history’s infamous rulers came to power – Napoleon. Construction on the fort finally began in the early 1800s, but it ended up taking more than 50 years for construction crews to finish. The storms that raged off the coast of France meant that they were working in perpetually dangerous conditions, and by the time Fort Boyard was built, it was already obsolete. New weapons technologies meant that the fort had outlived its usefulness before it was ever completed in 1859.

fort-boynard-france-3 (Image: Lapi)

After its completion, the maritime structure was turned into a prison until its abandonment in 1913. The sea fort changed hands several more times, sitting abandoned for decades. But obsolete or not, the fort continued to withstand the rough seas and violent storms that ravaged the area. It was only relatively recently that the abandoned sea fort fell into the hands of a creative production company who turned the old prison, which took more than two centuries to be realised from blueprints to opening, into the offbeat setting for a television show.

Fort Carroll, United States

The abandoned Fort Carroll, United States (Image: Lloyd Fox/Baltimore Sun)

Fort Carroll was built on an artificial island in the middle of the Chesapeake Bay, conceived as a defensive structure protecting Baltimore, Maryland. Construction began in 1847 and it wasn’t finished until 1900. Its usefulness was short-lived, though, and the planned defensive structure had already been rendered all but obsolete by advancements in warfare. Changes to the blueprints were made and the sea fort was renovated even as it was being built. But ultimately, it was abandoned.

The impressive form of Fort Carroll sits on a six-sided island, and covers almost four acres. Now privately owned, there have been a series of suggestions made for its re-purposing, including a casino and resort. Owners have long campaigned to get the island and its fort on a register of historic places, which will help not only preserve it, but secure funds for its restoration. There’s no denying that it’s a historic structure, but its history does present a problem.

fort-carroll-chesapeake-bay-maryland-2 (Image: John Stanton)

Fort Carroll is mostly famous for being built, rebuilt and remodelled; there were no major battles, no colourful characters, no ghost stories. The sea fort, in its abandoned state, has also been taken over by nesting birds, meaning that any plans to repurpose ut would require the destruction of the birds’ habitat – which is unlikely to pass any kind of government approval processes.

Brehon Tower, Channel Islands

Historic Brehon Tower, Channel Islands (Image: Unukorno)

The first structure to be built on Brehon Island was an obelisk in 1744. Intended as a day marker and navigational aid, the obelisk ended up a rather lonely structure that was all but useless. In order to increase the visibility of the structure, the obelisk was replaced by a 40-foot-tall tower in 1824.

Brehon Tower and the islands were the subject of renewed attention in the middle of the 19th century. The Channel Islands were high on the list of strategic locations for both Britain and France, and with the threat of war, it was decided that the site of the obelisk would be expanded into a sea fort. Work on the current Brehon Tower started in 1854, and by the time it was completed two years later the fortification had three floors, living quarters for a small garrison, and a gun platform on the roof.

brehon-tower-abandoned-2 (Image: Richard Stockwell)

The military tower remained in use through both World War One and World War Two, when it was manned by occupying German forces. Equipped with an anti-aircraft gun, Brehon Tower was responsible for bringing down multiple aircraft attempting to cross the Channel. After the war, the soon to the abandoned tower was emptied of all weapons and ammunition, and now its only occupants are sea birds.

Padmadurg, India

The military ruins of Padmadurg, India (Image: Shiv Chhatrapati)

Today, the abandoned sea fort of Padmadurg sits in ruins. It’s one of five maritime fortifications built by Chhatraparti Shivaji Maharaj, and in spite of being one of India’s great historical treasures, it’s falling increasingly into dereliction.

Padmadurg-Kasa-Fort-India-abandoned-2 (Image: Shiv Chhatrapati)

The fort was originally constructed in 1676; also known as the Kasa fort, it was built for the sole purpose of besieging another nearby fort – Janjira. The giant maritime structure sprawls over nine acres, and while it can still be seen from shore, it hasn’t been open to the public for some time due to the level of deterioration. Damage to Padmadurg sea fort began during its construction, when it came under attack even as it was being built.

Padmadurg-Kasa-Fort-India-abandoned-3 (Image: Shiv Chhatrapati)

Even those who have permission to visit the abandoned sea fort are restricted to certain areas; in its most recent history, Padmadurg was a stopover point for drug smugglers in the region.

While there are plans to restore the derelict fort, a lack of funds has largely put the proposals on hold. Those who are working in support of restoration cite not only the historical importance of the Padmadurg structure, but also the architectural beauty that’s slowly crumbling away.

Nab Tower, England

nab-tower (Image: 27col)

Nab Tower is a sort of eerie, abandoned mistake. In 1918, ships off England’s coast were being plagued by German U-boats. In an attempt to secure British waters near Southampton and Portsmouth, a plan was put in place to build a line of anti-submarine towers and connect them with netting, effectively blockading the English Channel. Only one – Nab Tower – had been built before the war ended; not only was there no more need for the towers, but there really wasn’t any use for only one in the proposed chain.

nab-tower-2 (Image: Trinity House)

Nab tower had been built in such a way that it was possible to tow it, a feature that saved the life of the lonely tower. It was decided that it would be used as a navigational aid and lighthouse, towed to its final location in 1920. The lower part of the sea tower was flooded, causing it to sink somewhat. As a result, the tower now lists slightly to one side, but it nevertheless remained home to lighthouse keepers for decades.

nab-tower-3 (Image: Stuart Buchan)

Lighthouse keepers lived on Nab Tower for two months on end, and at Christmas, whoever was pulling long, lonely duty at the time would be visited by local lifeboats carrying presents donated by the people of Bembridge. The long tradition of the lighthouse keepers ended in 1983, when the light was automated. The tower got a further upgrade in 1995, when it was converted to solar power. In 2013, a large portion of the old sea tower’s upper level was removed, shortening it considerably in a move deemed necessary to keep it safe. Nab Tower still serves as a lighthouse.

Humber Forts, England

humber-forts (Image: Jpacarter; the abandoned sea forts in the Humber estuary)

In 1915, two sea forts were built to defend the Humber estuary during the escalating troubles of World War One. Haile Sand Fort and Bull Sand Fort commenced operations in 1917 and 1919, built on massive concrete foundations with circular walls and steel plating.

The forts, which had been to designed to include all the living facilities needed for the men stationed there, were updated during World War Two with more powerful artillery. At the time of their construction, they were considered engineering marvels; both were based on solid concrete blocks that had been sunk beneath the ocean, forming interlocking piles that were filled with sand. At the height of their use, they were each home to around 200 people.

humber-forts-2 (Image: Neoskywalker)

Throughout World War Two, Humber forts were regularly attacked by both enemy aircraft and U-boats, but the decades-old structures that were considered engineering icons at the time still proved impenetrable.

The Humber sea forts were abandoned in 1956. There were a number of different uses put forward for them, but today, Haile Sand stands largely abandoned, though officially used as a navigational aid.

humber-forts-3 (Image: Chris)

Bull Sands, however, has been repurposed as a detox clinic. The abandoned sea fort in the Humber estuary has been officially renamed Island of Hope, destined to become the site of a detox clinic offered by the non-profit charity Streetwise. The facility have enough room for 240 people at any one time, and its location makes it the perfect place for the isolation and support needed by those recovering from their dependencies on alcohol or drugs.

Fort Alexander, Gulf of Finland, Russia

fort-alexander-russia (Image: Florstein; abandoned Fort Alexander)

Fort Alexander was built in the middle of the 19th century on an artificial island in the Gulf of Finland. It was officially pressed into service in 1845, but by 1860 the advance of rifle and artillery technology made the fort obsolete. Originally meant as a line of defence for St. Petersburg, the abandoned sea fort was repurposed as a military warehouse and storage facility.

By the turn of the 20th century, Fort Alexander had found a new purpose – quarantine. The plague was spreading throughout Europe, with epidemics sweeping through major cities. But medical progress was beginning to keep pace with advancements in warfare and doctors were now understanding how diseases worked – and how they could be combated. Fort Alexander was thus repurposed into a medical facility and plague research institute.

fort-alexander-russia-3 (Image: Витольд Муратов)

The former fort became home to researchers and doctors as well as a small military presence. It was also home to a menagerie of animals used for testing vaccinations – from horses and camels to rats and guinea pigs. Scientists worked to cure diseases like cholera and the bubonic plague, and, tragically, more than once the isolation of Fort Alexander proved useful as some scientists working there ultimately contracted the diseases they were trying to prevent. Because of the delicacy – and potential for disaster – of the diseases and viruses they were working with, security was just as tight as it had been when Fort Alexander was a military installation; there are records of bodies being burned in the old fort’s furnaces after researchers contracted various illnesses.

fort-alexander-russia-2 (Image: Армонд)

Fort Alexander was a medical facility until 1917, when it was emptied of all its medical equipment. The abandoned sea fort turned research centre has been largely deserted ever since, although the site does play host to the occasional concert, party, or music festival.

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About the author: Debra Kelly




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