History of Pendennis Castle
Pendennis Castle is one of England’s finest surviving coastal fortresses. With the castle at St Mawes, Pendennis guarded the anchorage of Carrick Roads and the port towns of Penryn, Truro and Falmouth for over 400 years. The castle began as a gun fort in the mid-16th century. Defences were added in the 1590s following the threat of Spanish invasion and were periodically updated, notably during the Second World War when the guns again saw action.
Henry VIII’s Artillery Fort
Pendennis Castle was built from 1540 to 1545 when England faced a possible invasion from the united powers of Catholic Europe. To defend against this, Henry VIII implemented a national programme of military and naval preparations, including new coastal artillery forts. These were equipped with guns to shatter enemy warships and troop transports that might attempt to capture English ports.
The important anchorage of Carrick Roads, a deep estuary at the mouth of the river Fal, was a perfect location for an enemy to establish a base. To protect it, Henry built gun forts on opposite shores, at Pendennis and St Mawes. Pendennis Castle had a circular design that allowed all-round fire from guns mounted at several levels.
The normal tiny garrison of about 15 was increased to 100 or more when there was an imminent threat, notably during the planned Spanish invasions of 1574, 1579, 1588 (the ‘Great Armada’) and 1596–97. On the last occasion, a Spanish fleet intended to land troops at Pendennis and capture Carrick Roads. The attack never came but the threat forced Elizabeth I to review the defences.
The Siege of Pendennis, 1646
1625–1630 saw England make a catastrophic attempt to influence the course of the Thirty Years War in continental Europe, mainly in opposition to Spain. This prompted improvements to Pendennis and in 1627, the engineer Sir Bernard Johnson constructed a new rampart and ditch (the Hornwork) across the peninsula, replacing a neglected Tudor earthwork and strengthening the land defences to the north.
Pendennis was tested during the First Civil War (1642–46), when Falmouth was an important port for King Charles I’s army. In 1646 Pendennis was one of the last Royalist strongholds to hold out against the Parliamentary army; about 1,000 soldiers and their dependents endured a three month siege, agreeing an honourable surrender in August when food supplies ran out.
Decline and Rearmament
After the defeat of Napoleon at Waterloo in 1815, Pendennis was neglected and many of the temporary buildings were removed. By the late 1850s, however, England and France were rivals again in a race for military and naval advantage. More powerful guns were installed at Pendennis from 1854, notably at Half Moon Battery and at Crab Quay, on the east side of the headland.
Yet the fortress received little attention in the nationwide programme of fort-building in the 1860s, being considered a lower strategic target for the enemy than many other locations around the coast.
Nonetheless, the outdated defences were gradually improved from 1880 to 1900, a period of revolutionary change in military technology. The first major development was a submarine minefield laid across the entrance to Carrick Roads in 1885, with mines that could be detonated remotely.
But it was Falmouth’s designation as a Defended Port in 1887 that resulted in many new defences for the estuary, commanded from Pendennis Castle. These comprised breech-loading guns (replacing the older, muzzle-loading guns), accurate range-finders, searchlights to aid night fighting and telephones and electricity to enable efficient communication. Six-inch guns – those firing sizeable shells with a six inch diameter – were intended to engage warships from new positions in One Gun Battery inside Pendennis and from Half Moon Battery, while light quick-firing 6- and 12-pounder guns to counter fast torpedo boats were fitted in East Bastion, Carrick Mount Bastion and Crab Quay.
Such intricate defences required a permanent staff and in 1902 new barracks were built at Pendennis for the 105th Company Royal Garrison Artillery. Other new buildings included a War Signal Station on the roof of the Henrician castle to control shipping movements.