Pendennis Castle was built upon on a peninsula jutting out into the Carrick Roads. It was constructed by Henry VIII as part of a nationwide upgrade of coastal defences and was substantially enlarged during the Elizabethan period. At the end of the Civil War, it endured a lengthy siege by Parliamentary forces. The castle remained in use until the end of WWII.
In 1534 Henry VIII sealed the Act of Supremacy which made him, rather than the Pope, "supreme head" of the English church. This caused outrage across continental Europe and, coupled with a rare period of peace between France and Spain, meant an invasion was a distinct possibility. The King embarked upon the biggest coastal defence programme since Roman times with over thirty castles, blockhouses and earthwork defences constructed. The Fal estuary, which had no existing fortifications, was identified as strategically important as it offered a large natural harbour and access far inland. Henry's commissioners considered that the site could be easily captured by a hostile force and used as a bridgehead to support an invasion. Accordingly two castles were commissioned - St Mawes and Pendennis - and together they provided artillery coverage across the one mile wide entrance into the Carrick Roads.
Pendennis Castle was built on a narrow peninsula jutting out into the Carrick Roads. Work started in October 1540 and cost £5,614. The first element to be built was probably Little Dennis, a small artillery blockhouse at the water's edge. This two storey D-shaped structure was equipped with three gun-ports. Construction of the main castle, which was situated on higher ground, followed straight after possibly under the direction of John Killigrew of Arwenack. Like other Henrician forts built at the same time, it was based upon a new concept in castle design; concentric circular gun platforms which enabled artillery fire in any direction. Compared to St Mawes, Pendennis was a relative simple affair with a single circular Keep surrounded by a low circular curtain wall. Nevertheless, this arrangement offered the castle four tiers of artillery - one in open embrasures on the curtain wall, two enclosed with the Keep and a further gun platform on the Keep roof. Earthworks provided protection against land attack.
Henry VIII's castle consisted of a circular tower surrounded by a curtain wall.
The invasion scare of the 1540s passed without incident. However, during the reign of Elizabeth I, religious and economic differences resulted in war between England and Spain. The English government feared a Spanish invasion and accordingly kept Pendennis Castle garrisoned with a force of 100 men. Little Dennis was also enhanced with a new battery adjacent to the blockhouse. The invasions fears were realised in 1588 when Spain sent a large Armada against England. This was defeated but the conflict continued and between 1593 and 1595 several raids were made on western Cornwall. These attacks encourage Spain to prepare another Armada which planned to seize control of the Fal estuary. Bad weather frustrated the attempt but it prompted the Government to review the defences at Pendennis Point. In 1597 work started on a new bastioned fortress surrounding the old Henrician castle. It was supervised by Sir Walter Raleigh and Sir Ferdinando Gorges, who had recently built Drake's Fort in Plymouth. The new fortress was completed in 1600 but shortly after the new King of England, James I, made peace with Spain.
During the Civil War, Cornwall was in the Royalist sphere of influence. Falmouth was critical to the King's war effort as it provided a secure port through which he could import war materials which could be paid for by Cornish tin. Accordingly Pendennis Castle was garrisoned although it saw no action until 1646. By this time the Royalist War effort was on the verge of collapse and Parliamentary forces were driving into the South West. Whilst St Mawes Castle was abandoned, Pendennis prepared for a siege as the Royalists desperately sought to maintain a foothold on the mainland. By May 1646 a Parliamentary force under General Fairfax had besieged the castle but the garrison held out for three months until a lack of food forced their surrender.
Britain and France were regularly at war throughout much of the eighteenth century. The defences at Pendennis were reviewed in 1714 and found to be in a "precarious condition" but it wasn't until 1732 that work started on upgrading them. The weapons of the fort were modernised at this time and new barracks and magazines constructed. Further upgrades were made in the late eighteenth century in response to the French Revolution. In particular the Little Dennis Blockhouse, along with its supporting battery, were decommissioned and replaced with Half Moon Battery. A new installation was also built at St Anthony Head. However, after Nelson’s victory at Trafalgar (1805), fears of an invasion reduced and Pendennis was utilised as a supply base for the British Army.
Half Moon Battery
After the end of the Napoleonic Wars in 1815, the defences at Pendennis were neglected. This remained the case until the 1850s when French re-armament prompted fears of a resumption of Anglo-French warfare. The batteries at Pendennis Castle were restored and more powerful guns, 32-pounders and 56-pounders, were installed. Additional guns were installed in the 1870s. In 1885, an electronically activated minefield was installed across the Carrick Roads which was maintained and controlled from newly built observation posts at Pendennis Castle.
World War I
During the First World War Pendennis Castle exercised command and control over coastal defence in West Cornwall whilst the Carrick Roads became a rendezvous site for convoys prior to crossing the Atlantic. The castle also resumed its role as a Supply depot for the British Army fighting on the continent. The Falmouth defences did not fire in anger during the war but the Germans did attempt to access the estuary: in September 1915 the Royal Navy sunk a German U-boat just off-shore.
World War II
After World War I the facilities protecting Falmouth were decommissioned and by 1939 all the heavy guns had been removed. They were hastily re-armed after World War II started and further defences, including a harbour boom across the Carrick Roads and anti-aircraft guns, were installed. Twin 6-pounder Quick Firing guns were also added to the fortification's armaments to deal with the threat of E-boats (fast motor torpedo boats). Several engagements were recorded between Falmouth's coastal defences and German E-boats.
After the War
Coastal defence was disbanded in 1956 as, by this time, aircraft fitted with guided weapons performed the same role. Accordingly the artillery fitted at Pendennis Castle was removed and the site was decommissioned as a military establishment. Thereafter it was placed in the care of the Ministry of Works.
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Pendennis Castle includes the fortification built by Henry VIII and the extensive earthworks and artillery defences that were added in the subsequent years. The sister castle of St Mawes and the later St Anthony Head Battery are visible across the Carrick Roads.
Pendennis Castle Layout. The castle was built on a narrow peninsula jutting out into the Carrick Roads. The name derives from Pen Dinas, meaning 'headland fort', which suggests the site had perhaps been an Iron Age promontory fort. The small Henrican fortification was greatly enlarged when the bastioned defences were built in the late-Elizabethan era.
Little Dennis. Probably built just before the main castle, the small blockhouse known as Little Dennis was a two storey, D-shaped artillery tower. It originally had three gun ports on the lower floor and lighter guns could also have been operated from the open parapets on the upper level.
Tudor Castle. When compared with some of the other Henrician forts of the period, Pendennis was a relative simple affair with a single circular Keep surrounded by an outer circular curtain wall. The design was similar to Calshot Castle.
Castles of Henry VIII. In 1539 Henry VIII initiated the largest coastal defence programme since the Roman era. This 'Device for the Protection of the Realm' included construction of 19 masonry castles as well as many smaller blockhouses and earthwork forts.
Tudor Gatehouse. The gatehouse was probably added during the Elizabethan upgrades and would have replaced a much simpler structure. The structure incorporated the Commander's apartments.
One Gun Battery (Bell Battery). This 6-inch Breach Loading gun was installed in 1895. Its carriage was designed to recoil the barrel down into the emplacement so the weapon could be reloaded in safety. Pistons then automatically returned the gun to its firing position.
Nine Gun Battery. This battery was added to the Elizabethan defences in the 1730s (the guns on display are late eighteenth/early nineteenth century versions).
Half Moon Battery. This battery was built in 1793 as it offered a commanding position over the Carrick Roads. It was paired with another similar battery at St Anthony Head.
Half Moon Battery. The battery remained in use up to and during World War II. The armament and camouflage seen today reflect that period.
Barracks. The Royal Garrison Artillery Barracks were built between 1900 and 1902.
Pendennis Castle is in the care of English Heritage and is a major tourist attraction. The site is found off Castle Drive to the east of Port Pendennis and is well sign-posted. There is a large car park close to the castle. In Summer a passenger ferry shuttles between Pendennis and St Mawes castles.
Castle Drive, TR11 4LP
Little Dennis Blockhouse