Calshot Castle was one of Henry VIII's coastal castles built to defend England from a French attack. Over the years the castle developed from its initial defensive role into the centre of a community. It was used as accommodation, a coastguard station, a major air base, a training centre, the centre of a major international air competition as well as now being owned by English Heritage while the buildings that surround it hold an activities centre. Calshot Castle, despite being on the end of Calshot Spit, a mile long narrow sand and shingle stretch of land that reaches into the mouth of Southampton Water, midway along the Solent, is easily accessible from land. Some of the best views of Calshot Castle however are from the sea – either from a yacht or the ferry to the Isle of Wight that passes close to the castle.

History

When King Henry VIII left the Catholic church in 1538, traditional enemies Francis I, King of France and the Emperor Charles V of Spain signed a peace treaty and were encouraged by Pope Paul III to invade England. In response Henry VIII began a national building programme of castles to defend England from invasion. The area around the Isle of Wight and the Solent were of special concern to Henry¹. Portsmouth held Britain's first drydock and the Royal Navy base, the Isle of Wight could be used to land a large invading army in preparation for a sustained invasion of the mainland and Southampton was England's third largest port and a rich prize in itself. Southampton's mediæval castle and walls were now outdated and an inadequate defence against ships armed with cannon, and so to defend Southampton from an attacking fleet, coastal castles armed with cannon were ordered to be constructed.

The Construction Of Calshot Castle

Lord Admiral and Earl of Southampton William Fitzwilliam and Lord St John William Paulet, first Marquess of Winchester² were given the responsibility of planning the defences of the centre and west of the Solent. After surveying the tides and landscape of the Solent, they recommended the building of four forts. Two on the Isle of Wight, at Cowes³ and East Cowes, one large coastal castle on the end of the Hurst Spit⁴, a promontory of land that guards the narrowest point in the Solent, as well as a coastal castle to be built on Calshot⁵ Spit, a thin spit of land on the west bank of Southampton Water that guards where Southampton Water, the tidal river from Southampton, meets the Solent, the stretch of water that separates the mainland from the Isle of Wight.

The location for Calshot Castle to be constructed on was chosen on the 18 March, 1539 and by the end of 1540 Calshot Castle was completed. The speed in which the castle was built shows the importance attached to it. Despite the speed of construction, Calshot Castle is incredibly well-made, designed as state-of-the-art in castle technology. The castle's stonework is laid out and put together with precision and skill. Calshot Castle has a thick central circular tower with three tiers of cannon behind a thick circular parapet, all of which were designed to deflect cannon balls shot at the castle and withstand any bombardment from enemy ships. Calshot Castle was built from stone and other materials from the dissolved monasteries at Netley Abbey and Beaulieu Abbey⁶. Although far smaller and simpler in design than the largest Henrician⁷ castles of the period, Calshot Castle was still listed as one of the ten 'great castles' Henry VIII planned of the thirty castles, forts and blockhouses constructed. Calshot Castle was armed with 36 cannon and garrisoned by a Captain, a deputy, eight gunners and five soldiers.

Castle Description

Calshot Castle is a castle consisting of a polygonal curtain wall containing 15 gun emplacements and a Keep that is octagonal on the bottom floor but cylindrical for the top two floors. Entrance to the castle was over a wet stone-lined sixteen-sided moat 9 metres wide and 2.5 metres deep. A drawbridge, now replaced with a metal bridge, was the only way into the castle, and through a gatehouse, later expanded to house a range of buildings.

The Curtain Wall

The curtain wall originally consisted of 16 sides containing 15 gunports which were arched over and the drawbridge on the remaining side. The gunports were protected by a high wall and covered over, however in 1774 the height of the wall was lowered and the covered gunports were converted into open-topped embrasures. Between the embrasures are firing steps to allow defenders to fire handguns such as muskets and rifles at enemy attackers should this be required. Five of the original gunports were later converted in 1896 into emplacements for the castle's searchlights. The position of the searchlights is now taken up by two of HMS Tiger's signalling lamps to give an impression of their appearance, and there are two replica Tudor cannon positioned to defend the entry to Southampton Water.

Gatehouse

The gatehouse, the castle's only entrance, is on the western side of Calshot Castle. The original gatehouse layout was simple. It had one room over the gate passage and a crenellated defensive roof level above. The gateway was protected not only by a drawbridge but also by a portcullis operated from the first floor room, where two gunports for small hand-held weapons, like arrow loops, can be seen. It is believed likely that Henry VIII's coat-of-arms was also displayed on the castle's gatehouse above the gate.

In the 1770s the castle's gatehouse was greatly expanded to provide more accommodation, initially for the castle's governor. This was done in a manner that avoided the loss of any defensive capability as only one window overlooks out of the castle – all the others overlook the castle's courtyard. The gatehouse was expanded and heightened – the crenel in the battlement overlooking the castle's drawbridge was converted into an opening for a window for a new second floor. This expansion covered one gunport on either side of the main passageway – these two gunports are the only ones to survive with their original Tudor shape as all other gunports were converted into embrasures when the curtain wall was lowered in 1774. In 1896 the gatehouse was extended once more, with a cookhouse, latrine and storerooms added to the gatehouse's south side.

Only the rooms on the ground floor of the gatehouse are at time of writing open to the public, and they house the castle's gift shop as well as displays on the castle's history.

The Keep

The Keep is the castle's dominant structure. The Keep is octagonal on the bottom floors but cylindrical above. The ground level of the Keep's exterior has a pair of recesses on each side – these originally housed shot and powder for the guns mounted in the courtyard's curtain wall. On the outside of the castle is the remains of a bracket which once held the castle's bell as well as the royal shield.

The basement, accessible through a new staircase and doorway, was extensively modified in 1896. It is believed that it originally resembled the vaulted basement at nearby Hurst Castle as the same team of builders built it, though to a smaller design. The basement originally housed the castle's provisions, including food, water, fuel and ammunition. Unlike other castles, Calshot Castle did not have its own well as all water in the area would be contaminated with the salt water from the Solent. In 1896 the basement was converted to house oil engines and generators for the castle's searchlights. The basement's floor was dug out, which initially made the basement higher until the basement roof was remade in a strong concrete layer in a lower position. In 1907 the oil engines were removed to an outbuilding outside the castle, and the basement once again housed the ammunition for the castle's guns.

The first floor, accessible up a small flight of stairs, has an appearance of a nineteenth century barrack room, complete with metal extending bed frames and shelves for personal possessions. The floor is two feet lower than in 1540; when the basement was converted in 1896 the basement's new concrete ceiling was at a lower height than previously, allowing the first floor to have a lower floor. Some of the original Tudor stonework in this room is red, evidence of the 1580s fire which devastated the Keep.

The second floor of the Keep now houses an information display about the Schneider Cup. This floor originally held some of the castle's heaviest guns however in Victorian times the floor was converted into a barracks. There is a garderobe built into the wall on the southeast side.

The roof has been extensively modified. The curved parapet designed to deflect shot and the gun embrasures were replaced in 1770 by a universal height parapet designed to protect soldiers armed with muskets and rifles. In 1907 the parapet was again modified to hold two 12 pounder QF guns on raised platforms, with ammunitions lockers beneath and the present flat concrete floor was laid. The 12 pounder QF gun emplaced on the castle roof is not the original gun. Although the gun is the same it has a different mounting and shielding as the gun was originally part of a Naval vessel's armament.

Neighbouring Coastal Castles

Southampton was later further defended by two more castles on Southampton Water built soon after, in 1544. The first, St Andrew's Castle, was built where the river Hamble joins Southampton Water. The site of this, to the west of Hamble Common, has been completed eroded now, but it is believed to have been more of a blockhouse than an actual castle, consisting of a tall square tower behind cannon on a lower semi-circular bastion facing the sea. Halfway between St Andrew's Castle and Southampton, Netley Castle was built on William Paulet's own land, using the stone from neighbouring Netley Abbey. This was similar in design to a smaller Southsea Castle and still exists now, although almost entirely altered, as an old people's home.

Up To The Civil War

After the threat of invasion subsided after the Battle of the Solent and invasion of the Isle of Wight in 1545, Calshot Castle was allowed to gradually fall into disrepair. By 1559 only ten cannon were fully serviceable. Soon after, Calshot Castle suffered from a serious fire in the Keep that had even reddened the Keep's stone walls. In 1584, under Queen Elizabeth I, the castle was repaired with new floors constructed in the Keep to replace those consumed in the fire, with 127 trees from the nearby New Forest felled for the purpose.

By the time of the invasion threat from the Spanish Armada the castle was fully prepared, with a garrison of a master gunner and seven gunners.

In 1642, during the Civil War, Parliamentary forces under the command of Captain Swanley captured Calshot Castle as well as Netley Castle and St Andrew's Castle. The cannon from these castles were removed and were used to threaten Southampton unless the city surrendered and pledged its allegiance to Parliamentary forces. Although Netley Castle and St Andrew's Castle were demolished to prevent their use by Royalist forces, Calshot Castle and its role in protecting the approach to Southampton Water was too important to lose and instead money was spent on repairing it and returning it to full active status.

After The Civil War

After the Civil War various threats from France and Spain ensured that Calshot Castle was kept fully prepared. During the War of Spanish Succession in 1702-1713, Calshot Castle had twenty-five operational cannon. After the Scottish Rebellion in 1715, Calshot Castle was surveyed by Captain Talbot Edwards who was in charge of the coastal defences of Portsmouth, the Isle of Wight and the Solent. After this threat subsided, in order to save costs, the castle along with other coastal defences was kept at a maximum of half its normal complement and so by 1725 only 13 cannon and a garrison of a master gunner and two gunners remained.

In 1774 the first major alteration to Calshot Castle occurred. The gatehouse was extensively widened in order to create new rooms for the castles' Captain, or Governor as the Captain was now known. The outer circular curtain wall was also lowered, removing the gun ports and adapting them into embrasures⁸.

During the Napoleonic Wars, after Nelson's victory over the French and Spanish fleet at Trafalgar the likelihood of any foreign invasion seemed remote, and so Calshot Castle was considered unimportant. So much so that after the Napoleonic War ended with the Battle of Waterloo, Calshot Castle became quarters for the coastguard⁹. Calshot, located halfway along the Solent and at the very tip of Southampton Water, was perfectly located for a Coastguard station. The castle was used as coastguard quarters, with the commanding officer living in the tower, married men living in the gatehouse and other coastguard cottages were later constructed nearby. In 1856 Calshot Castle was transferred into Admiralty ownership when the Admiralty took over control and the responsibilities of the Coastguard.

The Latter Half Of The Nineteenth Century

From the 1860s warship design underwent a revolution as new technology was developed. In 1860 HMS Warrior, the world's first iron hulled warship, was launched as a direct response to France's ironclad La Gloire. By 1870 the first torpedoes had been developed and by the 1880s the French Navy, Britain's traditional enemy, had large numbers of fast torpedo boats. Although Britain's navy was larger and superior to that of France, it was worried that a combined French and Russian fleet could, in what was termed a 'bolt from the blue', defeat the Royal Navy in a surprise attack. To counter this perceived threat the Admiralty encouraged the development of heavy guns capable of firing faster in order to hit the speedier targets that a fast torpedo boat would offer.

In order to defend the Solent, coastal forts were fitted with the new quick firing (QF) guns as well as searchlights¹⁰, to prevent sneaky night attacks¹¹. As Calshot Castle was too confined to be re-equipped with all the new QF guns required a new gun battery was built just south of the castle. This was built between 1895 and completed in 1897 and was armed with six QF guns. The castle itself was used to house three searchlights as well as the generators to create electricity. In 1907 two QF guns were installed on Calshot Castle's roof.

Another defence of Southampton Water was a boom defence – a physical barrier stretching across Southampton Water preventing enemy ships entering undetected. This was one of the earliest boom defences in the country and was a line of hulks, old disused ships, secured across the mouth of Southampton Water with four towers armed with QF guns and machine guns known as 'dolphins' defending them. In 1909 a new purpose built boom was used to replace the old ships. The boom stretched across from Calshot Castle and was also defended by elderly torpedo boats. By 1910 there were 10 officers and 154 other ranks stationed in Calshot to man the castle, gun battery as well as the dolphins – of which 3 officers and 85 men lived in the castle itself with the rest nearby.

Calshot Royal Naval Air Station

On 28 March, 1910 the world's first seaplane flew in La Mède, near Marseilles, in France, pilopted by Henri Fabre. Also in 1910 the first take-off and landing happened at the site which was to become Southampton Airport. By 1912, the year in which the first British seaplanes were built¹² the Admiralty were keen to explore the possibilities that aquatic aircraft offered and, as aircraft carriers had not yet been conceived of, instead visualised a network of air stations around the UK.

Calshot, being sheltered and near both Portsmouth and Southampton, was considered the perfect site for the waters around the Isle of Wight. The Isle of Wight after all was playing a major role in seaplane and flying boat development. It was at Cowes on the Isle of Wight that the prototype Bat Boat, Europe's first flying boat, was built by Saunders¹³. This was named after a fictional flying machine in Kipling's With The Night Mail, and in July 1913 it won the Mortimer Singer Prize for the first all-British aeroplane capable of making six return flights over five miles within five hours. It was also the world's first successful amphibious aircraft. This Bat Boat, and subsequent Bat Boats built by Sopwith with Saunders building the hulls including one which one the Daily Mail prize for the first aircraft to complete a round-Britain trip, were bought by the Royal Navy and stationed at Calshot Castle.

On 29 March, 1913 Calshot Royal Naval Air Station began, with three wooden sheds¹⁴ housing up to twelve seaplanes with the naval personnel housed in the nearby coastguard cottages and at Warsash¹⁵ across Southampton Water. The first commanding officer, Lieutenant Spencer Grey, commuted in to Calshot each day on his own private seaplane. At the time Winston Churchill was First Lord of the Admiralty and he had a keen interest in developing the role of the Royal Naval Air Service and purchasing aircraft for them. It is Winston Churchill who is credited with inventing the term 'seaplane'. He first took a seaplane flight from Calshot Castle on 28 August 1913, piloted by Timmy Sopwith who later taught Churchill how to fly.

Calshot Air Station was used until the Great War for experimental work. This included trials of wireless telegraphy from aircraft and radio pioneer Guglielmo Marconi lived near Calshot Castle. When the King reviewed the fleet in July 1914, 17 aircraft flew from Calshot, passing the Royal Yacht.

The Great War

Shortly before the outbreak of war, Lieutenant Spencer Grey was reassigned and Calshot was commanded by Squadron Commander Longmore. Calshot continued in its role of training new pilots but also began to experiment in techniques to spot U-Boats, launch torpedoes, drop bombs and fire guns as well as aerial photography. From the end of 1916 with the increase of German submarine activity, Calshot began regular anti-submarine patrols. There were established subordinate stations originally at Bembridge and Portland, and later at Polegate and Newhaven to combat the submarine threat. Aircraft from Calshot helped a Naval ship sink U19 on Portland Bill in 1916. On the 12th August 1917, a Wight Converted Seaplane built by J. Samuel White's on the Isle of Wight¹⁶ was the first aircraft ever to destroy a submarine when Sub-Lieutenant Mossop bombed the German U-boat UB32, for which he was awarded the DSC. By the end of the war Calshot based aircraft had spotted 42 submarines and sunk three.

After the end of the war the Royal Naval Air Service was abolished and merged with the Royal Flying Corps to become the Royal Air Force. In 1918 Calshot Royal Naval Air Station reverted to a training role, becoming the School for Naval Co-Operation and Aerial Navigation, now training in sea rescue and recovery, and the flights stationed at Calshot became 240 Squadron. On 5 February, 1922 Calshot School For Naval Co-Operation and Aerial Navigation was renamed RAF Calshot.

The Calshot Express

Calshot grew in importance during the Great War new buildings, especially hangars and slipways for the aircraft, were constructed and the few coastguard cottages nearby were no longer sufficient. Instead a new camp was constructed at nearby Eaglehurst with a narrow-gauge railway built initially to help ferry supplies to the building site but later to transport personnel.

This, known as the Calshot Express, remained in service until the end of the Second World War and sadly no longer exists. However one engine, Douglas, still survives and now runs at the Talyllyn Railway in Wales. The Talyllyn Railway was a big source of inspiration for Thomas The Tank Engine author Reverend Wilbert Awdry, who gave many of his narrow-gauge characters similar names to engines there that inspired them. The character of Duncan in the Railway Series is based on the former Calshot Express engine Douglas. Duncan is engine 6 in Mr Percival the Thin Controller's Narrow Gauge Railway in Thomas the Tank Engine And Friends. Duncan regularly appears in Thomas And Friends from series 5 onwards. Episodes of the television series Thomas And Friends that particularly star Duncan at time of writing include 'Duncan Gets Spooked', 'Dunki'n Duncan' 'Duncan And The Old Mine', 'Duncan Drops A Clanger', 'Duncan's Bluff', 'Duncan Does It All' and 'Duncan And The Hot Air Balloon'. In the books by Reverand Awtry he first appeared in The Little Old Engine, book 14 in the original Railway Series, first published in 1959.

The Schneider Cup

In 1912 Jacques Schneider donated a bronze cup trophy to the Aero Club de France with the aim to promote seaplane development. The rules of the competition were that entrants would represent their country and the winning country would host the next competition. Any country that won the Schneider Cup three times in succession would win it outright. The competition was originally held annually although occasionally this was changed to every two years. Britain had a reasonable amount of success in its early years, winning in 1914 with a Sopwith biplane. In 1922 Britain won for a second time with a Supermarine Sea Lion II, designed by R. J. Mitchell, who would later design the Spitfire, instrumental in the Battle of Britain. In 1923, when Britain hosted the Schneider Cup in Cowes on the Isle of Wight, America won, and America won again at the next event in 1925, in which R. J. Mitchell's Supermarine S4, despite setting a new seaplane speed record of 226mph, crashed shortly before the race. In 1926 Italy won and for 1927 R. J. Mitchell designed the S-5 for the competition held in Venice.

In order to meet the challenge of the 1927 Schneider Cup, the RAF High-Speed Flight was formed to practice and participate in the race, based at Calshot. For two months they practised for the race at Calshot, flying Supermarine S5 seaplanes designed by R. J. Mitchell before leaving for Venice. The S5s came in first and second places. On their return the High-Speed Flight continued practising in 1928 for the next competition, to be held in 1929 and based at Calshot. On 12 March, 1928, whilst attempting to set a new speed record, Flight Lieutenant Sam Kinkhead crashed into the Solent.

The British Air Ministry commissioned Supermarine to build two more seaplanes for the 1929 Schneider Trophy race. These, the Supermarine S6, considered the direct predecessor of the Spitfire, were the first aircraft he designed powered by a Rolls Royce engine. The 1929 contest was held over the Solent and hosted at Calshot Castle, and on Saturday 7 September 1929 over a million people watched the race, with the best vantagepoints being on top of Calshot Castle. Flight Lieutenant Waghorn raced the S6 around the seven laps of the course at a speed of 328mph to win. Five days later Squadron Leader Orlebar fly an S6 to break the air-speed record, flying at 365mph. Among those involved with organising the 1929 Schneider Cup competition at Calshot was Aircraftsman Lawrence Shaw, commonly known as Lawrence of Arabia. He worked on Calshot and nearby Hythe on developing high speed launches, which were used initially to tow disabled flying boats and later led to developing air-sea rescue craft. The Supermarine S6 is on display in the Solent Sky museum, Southampton.

In 1931, when Britain had the opportunity to defend its title and win the Schneider Trophy outright, the world's financial position had changed. With Britain in a recession the government was unable to finance developing a new aircraft for the race. The rich and patriotic Lady Houston saved the day by sponsoring Britain's team. She provided enough money for R. J. Mitchell to refine his S6 aircraft, rather than develop a new one, fitted with a more powerful engine. Two of the modified aircraft, known as the S6.B, were built and one piloted by Flight Lieutenant Boothman won the race at Calshot in 1931 at a speed on 340mph, winning the Schneider Trophy outright. Two weeks later Flight Lieutenant Stainworth flew the other S6.B at a record air-speed of 407.5mph, the first man to fly at over 400mph.

The Second World War

By the time of the outbreak of the Second World War Calshot was again prepared for military duty and anti-submarine patrols. In addition, Calshot was used to repair and service the Short Sunderland flying boats that were the backbone of Britain's anti-submarine and pilot rescue efforts. Calshot Castle itself was defended initially by 3 anti-aircraft guns mounted on a barge near the castle, and plans had been prepared to sink ships in Southampton harbour at the entrance to Southampton Water near Calshot Castle should a German invasion attempt seem imminent.

In 1940 two 12 pounder QF guns were installed on the roof of Calshot Castle as well as six searchlights, with two more 12 pounder QF guns and six searchlights on the opposite shore of Southampton Water, at a location known as Bungalow Battery. Three miles southwest of Calshot Castle three 6-inch guns were installed at a site known as Stone Point Battery. These three sites made up Calshot Fire Command. Calshot Castle managed to escape heavy damage during the war despite Portsmouth and Southampton being among the Luftwaffe's top targets.

Soon after the war Calshot's Short Sunderland flying boats came to the rescue of the German people during the 1948 Berlin crisis, when Short Sunderlands airlifted food into Berlin and evacuated sick children to safety.

After the War

After the war the development of airports made flying boats all but obsolete. In 1953 Calshot Castle was closed as a frontline station and transferred to Maintenance Command, and on 1 April 1961 Calshot Castle closed as a Royal Air Force station. A purpose built coastguard tower was constructed next to Calshot Castle, and so the castle was no longer even needed as a Coastguard station.

Although in the 1940s flying boats continued flying commercially, the end was in site. In 1950 BOAC flew its last flying boat from Southampton. The Princess, the world's largest successful flying boat, first flew on the 22nd August 1952. Sadly, however, although many customers had originally expressed an interest, including BOAC and the RAF, none of the original three aircraft constructed were purchased. Between 1952 and 1967 two Princess flying boats were stored at Calshot, dwarfing the castle. In 1958 the US Navy were reported to be considering ordering the construction of a nuclear-powered version, yet in 1959 decided to cancel. In July 1967 the Princess flying boats were taken from Calshot Castle to be scrapped.

Calshot's last involvement with flying boats occurred in the 1980s. In 1981 a Short Sandringham flying boat, named The Southern Cross, flew to Calshot after crossing the Atlantic. This was restored and is now preserved in the Solent Sky museum, what was then the Southampton Hall of Aviation. In 1984 ML814, the last flying Sunderland of the 749 built, came ashore to Calshot to be refitted and restored. Sadly it left on 20 July 1994 and was flown to Florida to join the Fantasy of Flight private collection.

Since the opening of the Coastguard's neighbouring purpose built facilities meaning the castle itself was no longer required, Calshot Castle has been opened to a public. It has been restored to a pre-1914 appearance and is managed by English Heritage.

Other English Heritage properties nearby include Portchester Castle in Hampshire as well as Carisbrooke Castle and Osborne House on the Isle of Wight.

Calshot Activities Centre

The rest of Calshot Spit, including some of the former aircraft hangars, became what is now known as the Calshot Activities Centre on 25 November 1963. This is an educational outdoor pursuit facility. In 1964 sailing and canoeing facilities were opened followed by Britain's first indoor cycle track in 1967. Today as well as water-sports including windsurfing there are also sports pitches, climbing walls, ski slopes and high ropes course.