Royal Naval Museum



History of the Solent Forts


The four Solent forts were built for the protection of Portsmouth and it's harbour from sea attack and bombardment. The most likely "enemy" was the French.  At the same time, land forts in Gosport and Portsdown were also built to counteract any other land or sea attack. They were never used in anger and have become known locally as "Palmerston's Follies" after the Prime Minister of the time. Horse-Sands, No Mans Land and St Helen's were constructed between 1865-80. Spitbank was started two years later in 1867. Another fort, on Ryde Sand, was abandoned after construction had started due to unstable foundations.

In 1848 Louis Napoleon, nephew of Bonaparte, became President of the French Second Republic. In 1852, he seized complete power and declared himself Emperor Napoleon III. His ambitions, including the large army at his disposal, aroused concern in Britain, culminating in general public panic and clamour for the government to do something to protect the country from invasion. However, these initial plans did not materialise and in 1854, Britain joined a temporary alliance with France in war against Russia but suspicions remained about French intentions after the war. During the Crimean War, shortcomings of the British Army had been highlighted and the value of good fortifications proved.

The British government set about addressing the situation in the Solent. In 1857, it was proposed that three land forts were to be constructed between the existing Forts Elson and Gomer, the Hilsea Line's fortifications were to be rebuilt at the edge of Portsea Island and additional works along the Southsea coast to be constructed.

With the advances in steam propulsion, defence policy of old, where warships could maintain a close blockade on enemy ports, was no longer viable. Additionally, advances in ordnance manufacture had improved range and accuracy, giving an enemy the chance of bombarding coastlines from the sea and out of the range of coast defences. The government set up a Royal Commission into the issues and their conclusions were that a ring of new detached sea forts should be constructed. The conclusions were debated in Parliament and the Fortifications Act passed in 1860. However, two of the forts, including Spitbank were struck from the plans but under pressure, they were re-instated two years later.

The forts were designed by Captain E H Steward, who was part of the staff of the Assistant Inspector General of Fortifications, Colonel W F D Jervois. The ironwork and shields were designed separately by Captain Inglis and Lieutenant English. The noted civil engineer, Sir John Hawkshaw advised on the provision of foundations. Spitbank Fort was completed in June 1878, and St Helen's shortly after. The two outer forts, Horse Sand and No Mans Land, although started earlier, were completed in the spring of 1880. Horse Sands and No Mans Land are identical, being 200 ft in diameter and fully armour plated; the other two are only 150 ft diameter and iron plating on the front only.

The cost of building the forts was: (totals exclude armaments)

Horse Sand Fort - £424,694

No Mans Land Fort - £462,500

Spitbank Fort - £167,300

St Helen's Fort - £123, 311

By the time the forts had been completed, the "invasion" scare had long since passed and although the forts were armed and re-armed as technology advanced, they were never needed in the capacity in which they had been planned for. Even though they were armed during the First World War, two were used as naval signal stations and a line of concrete blocks and piles protected the coast and harbour from enemy attack. After suffering years of neglect, there was not a great role for the forts during the Second World War either. They were not able to support heavy anti-aircraft guns for general air defence. However, they were brought to war-readiness for the seizure of French warships anchored off Portsmouth in 1940, after the fall of France. This was the only time that their armament was trained on the targets for which they had been originally built. The seizure was completed with little opposition and actual firing from the guns on the forts was not necessary.

The forts were de-activated after the war and used for coastal artillery until 1956. In the 1960s, they were put up for sale - but not sold until the 1980s. Spitbank Fort was bought by a private buyer in 1982, restored and opened to the public. No Mans Land Fort was bought by a property company with plans to convert it to a luxury home, complete with private heli-pad. It is believed that St Helen's Fort was sold, but no information on the purpose or by whom is available. Horse Sand Fort was taken off the market and retained by the Ministry of Defence.

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©Royal Naval Museum Library, 2005

The information contained in this information sheet is correct as far as we are able to ascertain from our sources. It is not intended to be an exhaustive or complete history of the subject. Please contact the library for a bibliography of further reading materials, if available