Maunsell Sea Forts

Located off shore on the Thames estuary, the Maunsell Sea Forts are some of the most bizarre-looking structures. They are named after the civil engineer that designed them, Guy Maunsell.

The forts had a very short but intense life during World War II when Great Britain faced serious attacks from the Luftwaffe. There was little that could be done on land to counteract the on-going attacks on the naval infrastructure.

Maunsell Sea Forts

The Maunsell Sea Forts were built in 1942 and decommissioned in the 1950’s. They were left abandoned in 1958 but some of them still stand to this day.

Although collectively known as Maunsell forts, there are two distinct designs with different purposes. Closer to the mainland there were three-three army forts on the Thames estuary and on the Mersey. Further offshore there were another four naval forts in the Thames estuary. The army forts consisted of seven circularly shaped forts that were connected through a walkway. The naval forts have two cylindrical towers that are united by a gun platform above.

The Naval Forts

The first forts to be deployed were the four naval forts that were built between February and June 1942. These forts housed 120 men each, mostly below the waterline. These structures were built onshore and sunk into their position offshore. The naval forts were single structures that had seven floors. Each fort had Bofors guns and a radar.

Out of the original four naval forts only two survived to this day. One of these last two forts currently hosts the self-proclaimed Principality of Sealand.

The Army Forts

In 1943 Guy Maunsell designed a new type of fort that looked more futuristic. Each fort consisted of a central control tower linked to six “satellites”.

Out of the three army forts situated in the Thames estuary, the Nore Army Fort was closest to the shore. This army fort is the only one that no longer exists as it was badly damaged during the 50’s and was demolished by 1960.

The Red Sands army fort is made up of seven forts that were linked by walkways. There is an on-going effort to restore the Red Sands army forts because they are considered to be in the best condition.

Located over 9 miles away from the shores, the Shivering Sands Army Fort currently stays abandoned. Out of the seven forts built here, only six stand today after one of the forts was hit by a Norwegian boat in 1963. It served as the location of the first pirate radio that broadcast from the Maunsell forts. Its future is uncertain but there are plans to dismantle it.

Right after the war they were put under maintenance, but soon they lost any strategic importance and were used in different ways. To learn more about the stories of the forts head to the page about Maunsell Sea Forts History.

Maunsell Boat Trips

In the past there were plenty of boat tours that approached the Maunsell Sea Forts and even let people take a look inside of them but nowadays organized tours are rare.

Currently it is dangerous to climb to the forts because the stairs have been removed and most of the structures are in an advanced state of decay.

In the past most of the trips departing to the Maunsell sea forts commenced from the nearby Herne Bay.

Operation Redsand Forts performs regular boat tours to the forts. A return ticket price costs £60 and their exact schedule can be found on their site.

Today, daily tours are performed by a restored Thames sailing barge. Built in 1892 the Greta explores the Maunsell Forts at a very leisurely pace. The 6 hour tours of the Thames estuary commence at Whitstable Harbour, just seven miles north of Canterbury.

Non-regular services are also offered by X-Pilot but you need to call to inquire about the dates the boat goes to the Maunsell forts.

The people at Project Redsand also do regular trips to the Redsand Army Fort for maintenance work. If you want to go to a trip with them and volunteer see Project Redsand for available dates.

Maunsell Sea Forts History

Originally 49 sea forts were planned to be built on the Thames estuary and 38 on the Mersey.

The forts were built on land and transported out on the sea.

Right after they were planted there, they became operational and took part in the British effort to defend the much-so important Thames Estuary.

After the war was over the forts lost their strategic importance and were soon decommissioned.

The Nore Army Fort had to be dismantled between 1959 and 1960 after two of the towers collided with a ship and the ruins were considered unsafe.

Possibly the other towers would have been forgotten as well but musician and troublemaker Screaming Lord Sutch founded Radio Sutch in 1964.

The pirate radio started in a fishing boat but in May it relocated in the ruins of Shivering Sands fort. Although Sutch soon sold the radio station to his manager, many other pirate radios moved in to other forts and started broadcasting from there.

Some of these pirate radios include Radio 390 on Redsands, Radio Essex on Knock John or Tower Radio on Sunk Head. Soon after the Marine Broadcasting Act passed and offshore pirate radios were outlawed. As a response BBC started Radio 1 and Radio 2 in 1967.

Aspects of the forts’ design were used in the early 70’s for offshore oil and gas rigs and they are considered as the predecessors of modern offshore rigs.

The Roughs tower is occupied by the Principality of Sealand since 1967, a micronation that is described as the world’s smallest country.

In 1996 following a heavy storm, Tongue Fort collapsed.

Currently the Redsands Project aims to restore the Redsands Army Fort.

Among the renovation plans are an on-site museum devoted to the war and the pirates, a recording studio, and possibly a broadcasting studio.

Guy Maunsell

Guy Anson Maunsell was the civil engineer responsible for designing the sea forts that bear his name. He was born in 1884 in British India to a military father.

He was sent to school to the Eastbourne College in 1897 and later he studied civil engineering at the City and Guilds of London Institute.

During World War I he spent a year as an officer of the Royal Engineers on the western front.

He was involved in designing eight anti-submarine towers named M-N next to Dover Strait.

He is best known for his forts designed on the Thames estuary during World War II.

After the war he has founded his own company, G Maunsell & Partners which used prestressed concrete for many structures.

He died in 1961 at the age of 76.

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