Castles, forts and batteries: how Cornwall was defended through time from the land, the sea and the air.

 


The Threat from the Sea

 

Introduction

Pendennis Castle guarding the approaches to Falmouth. The headland at Pendennis is likely to have been used as a cliff castle in prehistory; its name is derived from the Cornish for ‘fort on the headland’.  From the sixteenth century onwards the natural harbour at Falmouth was seen as strategically important. This artist’s reconstruction shows Henry VIII’s fort enclosed by the Elizabethan curtain wall and six-point bastion, and Pendennis Point with its blockhouse at the bottom right corner of the image. © English Heritage Photo Library  Pendennis Castle guarding the approaches to Falmouth. This artist’s reconstruction shows Henry VIII’s fort enclosed by the Elizabethan curtain wall and six-point bastion, and Pendennis Point with its blockhouse at the bottom right corner of the image.  © English Heritage Photo Library

 

From the Norman invasion of England until the fifteenth century, castles were sites from which a small number of militia could control the surrounding area. They were strategically placed throughout the country in order to control it from within. They also served as protection from neighbouring hostile groups in a politically unstable realm.

 

By the Tudor period, from the reign of Henry VIII to that of Elizabeth I, the main threat to England’s security was from abroad. The position of Cornwall and Scilly was of immense strategic importance, guarding the western approaches to the Channel.

 

From the Tudor period onwards, continual programmes of defence building along the Cornish coasts were undertaken. During the first half of the sixteenth century Henry built a string of small artillery forts, known as blockhouses, stretching from Scilly in the west to Mount Edgcumbe in the east. The deep water harbour at Falmouth was protected with two larger fortresses at Pendennis and St Mawes.

 

Elizabeth strengthened the fort at Pendennis by adding a massive bastioned earthwork, and commissioned the construction of Star Castle on Scilly. These fortifications were enhanced during the eighteenth century, when many of the nationally important defences on St Mary’s, Scilly’s main island, were built.

 

The threat of invasion by France at the end of the eighteenth century led to the rearming of existing coastal fortifications, the building of a series of redoubts at Maker Heights, overlooking Plymouth Sound and the construction of a new coastal battery on St Anthony Head to bolster the defences of Falmouth.

 

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The Tudors: Henry VIII

The well-preserved blockhouse known as Little Dennis, at the foot of Pendennis Headland, formed part of the defences of the natural harbour at Falmouth. This artillery fort was built by Henry VIII in during the 1540s. Photo © Cornwall County Council Historic Environment Service The well-preserved blockhouse known as Little Dennis, at the foot of Pendennis Headland, formed part of the defences of the natural harbour at Falmouth. This artillery fort was built by Henry VIII during the 1540s. Photo © Cornwall County Council Historic Environment Service

 

Increasingly during the late medieval period, English security was threatened from abroad. During and beyond the Hundred Years War (1338 – 1453), the towns on the Channel coast were frequently raided by the French. Later in the sixteenth century there was a constant, if low level threat from Barbary Corsairs from North Africa predating on the fishing fleets and coastal trading ships.

 

This prompted the building of coastal defences in Cornwall and elsewhere. The most substantial of these were small artillery towers known as blockhouses. They are among the earliest examples of fortifications purpose-built to house artillery. Blockhouses were sited to cover strategic positions, and at least three in Cornwall were built before 1500.

 

One, built around 1490, was situated on St Ives Island but has now been demolished. Two others still survive; these are the pair of structures that defend the entrance to the harbour at Fowey. They are two-storey, stone-built structures each with two gun-ports. They were built in the late fifteenth century and sat at either end of a heavy chain stretched across the harbour. Their construction was funded by the Treffrys, a wealthy local family. Elizabeth Treffry is said to have poured boiling oil over the heads of French pirates when they attacked the port.

 

The blockhouse at Old Grimsby, Tresco, Isles of Scilly. Dating from 1544, it is built on a natural Carn and consists of a paved platform reached by stone steps. This platform is enclosed by a parapet and has two gun embrasures. The blockhouse is positioned to guard the natural harbour at Old Grimsby and was re-used by Royalist forces during the Civil Wars (1642 – 1651). © English Heritage: NMR23934/19 The blockhouse at Old Grimsby, Tresco, Isles of Scilly.  The blockhouse is positioned to guard the natural harbour at Old Grimsby and was re-used by Royalist forces during the Civil Wars (1642 – 1651). © English Heritage: NMR23934/19

A new blockhouse overlooking the two earlier structures at Fowey was built at St Catherine’s Point (c.1540) during the main phase of blockhouse construction in the first half of the sixteenth century. A small square tower was constructed on the shore at Mount Edgcumbe around 1540. Most were built by Henry VIII, the second Tudor king. During his reign from 1509 to 1547, he energetically built up an effective navy which began to challenge the maritime supremacy of Spain. He also oversaw an extensive programme of coastal defence building. As part of this programme blockhouses were sited all along the south coast of Cornwall and in the Isles of Scilly.

 

 

 

St Mawes Castle guarded the east side of the harbour entrance at Falmouth. From the late 1500s, St Mawes Castle became less important than Pendennis because it was indefensible from landward attack. Despite this, St Mawes has been used as a defensive base continuously since the sixteenth century.  Photo © Cornwall County Council Historic Environment Service St Mawes Castle guarded the east side of the harbour entrance at Falmouth. From the late 1500s, St Mawes Castle became less important than Pendennis because it was indefensible from landward attack. Despite this, St Mawes has been used as a defensive base continuously since the sixteenth century.  Photo © Cornwall County Council Historic Environment Service

In the 1530s and 1540s Henry built a series of forts, known as Device Forts, along England’s southern coasts.

 

Unlike earlier castles these were definitely not intended to double as high-status residences. Their purpose was to make use of naturally defensive features along the coastline to protect important strategic centres from attack.

 

The forts were designed to house heavy artillery and at the same time blend into the landscape, making them difficult targets for enemy vessels.

 

About thirty forts were built altogether along England’s south coast; those at St Mawes and Pendennis, guarding the deep water harbour at Falmouth were among the most important.

 

The Isles of Scilly were particularly important as the most westerly anchorage and first landfall for naval ships and merchantmen. King Charles Castle was built between 1548 and 1554 to defend the anchorage at New Grimsby.  The construction of a fort (Harry's Walls) was begun on St Mary’s to defend the harbour but was never completed, and three blockhouses were built on the Islands. 

 

A large blockhouse or artillery fort on Castle Down, Tresco. The fort is known as ‘King Charles’s Castle because it was re-used during the Civil Wars (1642 – 1651). It was built during the early 1550s to defend the harbour at New Grimsby. The fort was semi-hexagonal in shape; a design which provided a wide field of fire. It was originally two-storeyed to accommodate two tiers of guns covering the harbour entrance. Photo © Cornwall County Council Historic Environment Service A large blockhouse or artillery fort on Castle Down, Tresco. The fort is known as ‘King Charles’s Castle because it was re-used during the Civil Wars (1642 – 1651). It was built during the early 1550s to defend the harbour at New Grimsby. The fort was semi-hexagonal in shape; a design which provided a wide field of fire. It was originally two-storeyed to accommodate two tiers of guns covering the harbour entrance. Photo © Cornwall County Council Historic Environment Service

 

The increased use of heavy canon during the late fifteenth and sixteenth centuries led to a new style of fortification. Curved or angled sections of walling that projected from an enclosing curtain wall provided flanking fire from gun emplacements set within them. This type of projection from a primary wall is known as a bastion. The greater the range of fire from each bastion, the more effective a defence it provided. The bastion design is characteristic in several of Cornwall’s fortresses from this time.

 

The partially built sixteenth century fort on Mount Flagon, St Mary’s, Isles of Scilly. Although named ‘Harry’s Walls’ the building dates from 1551, during the reign of Edward VI. Its plan – square with angled bastions at each corner - was based on an Italian design reflecting the increasing use of canon. Poor siting is probably the reason why work was abandoned on the fort. © English Heritage: NMR 23940/09 The partially built sixteenth century fort on Mount Flagon, St Mary’s, Isles of Scilly. Although named ‘Harry’s Walls’ the building dates from 1551, during the reign of Edward VI. Its plan – square with angled bastions at each corner - was based on an Italian design reflecting the increasing use of canon. Poor siting is probably the reason why work was abandoned on the fort.  © English Heritage: NMR 23940/09

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The Tudors: Elizabeth I

Pendennis Castle. The headland has been repeatedly refortified over the centuries. The massive earthworks comprise a six-point bastion dating from the reign of Elizabeth I. Heavy canon would have been mounted on each point of the bastion, thereby affording huge firepower over a wide area. © English Heritage: NMR18430/16 Pendennis Castle. The headland has been repeatedly refortified over the centuries. The massive earthworks comprise a six-point bastion dating from the reign of Elizabeth I. Heavy canon would have been mounted on each point of the bastion, thereby affording huge firepower over a wide area.  © English Heritage: NMR18430/16

 

Major enhancements of the coastal defences were undertaken during the reign of Elizabeth I (1558 – 1603) the last of the Tudors. In the 11 years since the death of her father, Henry VIII, England had become torn by opposing factions, the Treasury was empty, and the country was riven by religious fears and differences.

 

Elizabeth was a moderate Protestant; following the massacre of the Huguenots she sent an army to support the French Protestants and she assisted the Spanish Netherlands (present-day Belgium) in its struggle for independence from Catholic Spain. She also refused an offer of marriage from Philip of Spain. Enraged, Philip saw the defeat of England as a crusade and launched the Armada in 1588.  Following its defeat Elizabeth embarked on a substantial programme of fortifications.

 

Plymouths’ defences were updated and guns installed at Mount Edgcumbe and Cawsand on the Cornish side of Plymouth Sound. Existing defences elsewhere on the coast were strengthened. At Pendennis (1598 - 1600), for instance, an outer line of defence on the landward side of the castle was constructed and the Henrician Device Fort was surrounded by a massive bastioned earthwork and curtain wall. This type of fortification is known as an ‘enceinte’.

 

During this period a bastioned defence was built on St Ives Island facing the town and a battery constructed to control the channel to the entrance of Padstow harbour.

 

By the 1590s the existing defences of Scilly were clearly inadequate in the face of Spanish privateering and the threat of a second invasion fleet. From this date onwards the focus of military activity on the main island, St Mary’s, was The Hugh, a promontory overlooking the deep water channels to the island’s main harbour. This is reflected in the promontory subsequently being renamed the ‘Garrison’

 

Star Castle, St Mary’s. Each of its eight points provided oblique fire covering the ground immediately in front of the works, so that a complete blanket of fire could be achieved. Star castle served as a prison as well as a fortress and is now an hotel. © English Heritage: NMR 23939/25 Star Castle, St Mary’s. Each of its eight points provided oblique fire covering the ground immediately in front of the works, so that a complete blanket of fire could be achieved. Star castle served as a prison as well as a fortress and is now a hotel.  © English Heritage: NMR 23939/25

 

In 1593 an artillery fort, Star Castle was built on the Garrison for Elizabeth by Francis Godolphin, the island’s governor. The castle is in the shape of an eight-pointed star surrounded by a dry moat. A stone bridge over the moat leads through a projecting gatehouse which would have been closed by a portcullis.

 

The Garrison is connected to the rest of St Mary’s by a narrow isthmus. Around 1600 a curtain wall was built across the land approach from the isthmus. A number of gun batteries were incorporated into the line of the curtain and it had a gateway, and three sally ports (discreet exits which allow the defenders to "sally forth" and engage the attackers), one of which is still in use.

 

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The Eighteenth Century: the rise to Empire

The eighteenth century Garrison walls, St Mary’s, showing King George’s battery. Photo © Cornwall County Council Historic Environment Service The eighteenth century Garrison walls, St Mary’s, showing King George’s battery.  Photo © Cornwall County Council Historic Environment Service

Throughout the seventeenth and eighteenth centuries Britain was involved in many colonial and continental wars; most of these conflicts were with France.

 

In the early 1700s a new battery was established at Crab Quay on Pendennis Headland and existing defences here and elsewhere were refurbished in response to successive invasion scares.

 

Eighteenth century military works are particularly well-preserved on the Garrison in the Isles of Scilly. During the Spanish Wars of 1715–1750 the defences of the Garrison were transformed.

 

The Elizabethan curtain wall dividing the Garrison from Hugh Town was rebuilt and was extended around most of the headland. The curtain wall was capable of mounting 120 guns, and the sea approaches were covered by batteries and large bastions. The Garrison Gate was rebuilt in 1742 as was the magazine, known as the Rocket House, a sunken building surrounded by a blast wall.

 

The curtain wall on the southern side of the Garrison. The approaches to Hugh Town are covered by two large bastioned gun batteries; Woolpack Battery (in the centre of the photo) and Morning Point Battery (to the right). In between these batteries are a series of ‘redans’; mini-bastions or salient angles from which soldiers could provide flanking fire. Outside the walls, between the redans are overgrown plots used by the soldiers to cultivate crops. © English Heritage: NMR 23938/11 The curtain wall on the southern side of the Garrison. The approaches to Hugh Town are covered by two large bastioned gun batteries; Woolpack Battery (in the centre of the photo) and Morning Point Battery (to the right). In between these batteries are a series of ‘redans’; mini-bastions or salient angles from which soldiers could provide flanking fire. Outside the walls, between the redans are overgrown plots used by the soldiers to cultivate crops.  © English Heritage: NMR 23938/11

 

Substantial improvements were also made at Falmouth with new batteries at Pendennis and St Mawes. Three new batteries were added to the Fowey defences including an improved one at St Catherine's Castle, and the Plymouth defences strengthened at Cawsand and at Redding Point, Mount Edgcumbe.

 

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Revolution and War

Cornwall’s defences were strengthened by the Duke of Richmond in the 1770s and 1780s as a precaution against the rise of the American Navy during the American War of Independence. He built redoubts and barracks at Maker Heights in East Cornwall, and these were further strengthened during the Napoleonic wars. Maker Heights were considered a vulnerable point in the defence of Plymouth because their raised position could be utilised by an attacking force to bombard the docks.

 

Carrick Roads and the approach to Falmouth Harbour from the southeast. In the foreground is St Anthony Head which held a coastal gun battery from the eighteenth century. Photo © Cornwall County Council Historic Environment Service Carrick Roads and the approach to Falmouth Harbour from the southeast. In the foreground is St Anthony Head which held a coastal gun battery from the eighteenth century.  Photo © Cornwall County Council Historic Environment Service

The French Revolution of 1789-1799 saw radical changes in French government. France had previously been an absolute monarchy. Idealist principles of citizenship and democracy, fed by the Age of Enlightenment, led to the Reign of Terror of 1793-4. This was a year of mass executions and violent upheaval throughout the country.

 

An initially sympathetic response in Britain to the French Revolution turned to alarm at the executions of French aristocrats and clergy. In 1793 the French ambassador was expelled and France declared war on Britain. The rise of Napoleon Bonaparte during this period led to him heading an army poised to invade Britain at the end of the eighteenth century. Napoleon’s invasion plans suffered a severe setback in 1805 when his fleet was defeated at the Battle of Trafalgar, and were ended in 1815 by the French defeat at Waterloo.

 

Preparations in Britain against a French invasion led to the strengthening and modernising of existing defences, and the building of new defences.  Coastal batteries were built at Padstow, Portreath, St Ives, Whitesand Bay, Penzance, Mousehole, Mount's Bay, St Michael's Mount, Mevagissey, Charlestown and Looe.  At Falmouth, Crab Quay battery was rebuilt, the blockhouse at Little Dennis was rearmed, as was that below St Mawes Castle, and a new, crescent-shaped battery, Half Moon battery, was built on Pendennis Headland. A naval dockyard was built at Mylor in the Fal Estuary and this served as a base for blockades of the French Breton ports. A new coastal battery was built at St Anthony Head which substantially increased the covering fire over Falmouth Harbour.

 

The Fowey defences were substantially upgraded with six operational batteries ready for action, whilst the defences at Plymouth were massively expanded on the Cornish shore.  The pre Napoleonic redoubts on Maker Heights were extended and waterline batteries built to protect Cawsand Bay as well as the approaches to Plymouth Sound. Many of these still survive to be explored.

 

Maker Heights, overlooking Plymouth docks. two centuries of fortifications. A large eighteenth century redoubt is visible in the lower centre of this photo. In the left is a line of three more redoubts. Later fortifications at Maker Heights include late Victorian batteries and a Second World War anti-aircraft battery. © English Heritage (NMR) RAF Photography: CPE/UK/1890/2137 Maker Heights, overlooking Plymouth docks. two centuries of fortifications. A large eighteenth century redoubt is visible in the lower centre of this photo. In the left is a line of three more redoubts. Later fortifications at Maker Heights include late Victorian batteries and a Second World War anti-aircraft battery. © English Heritage (NMR) RAF Photography: CPE/UK/1890/2137

 

A characteristic of defences from the Napoleonic period, and the late eighteenth century generally, is the use of redoubts as strongpoints. A redoubt is an enclosed defensive work lying outside a fort, and without angular projections (bastions) in its outline. Redoubts were most commonly four or five-sided, and were usually earthworks, although some later ones were of stone or brick. The advantage of the redoubt design is that it was relatively easy to lay out on the ground and could be constructed quite quickly.

 

The 1860s saw the beginning of a huge fort building programme around the major ports and naval bases. Before this, a series of coastal batteries manned by volunteer companies (to match the volunteer rifle and cavalry companies) were formed around the coast of Cornwall.  In some cases such as at Padstow, Looe, Fowey, Charlestown, Penzance and St Ives existing batteries were re used whilst at Marazion, Hayle and St Just new batteries were constructed.  The batteries at St Ives, Padstow, Charlestown, Fowey and St Just still survive.

 

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