The area around Portsmouth has been the site of a naval base for centuries, even as far back as Roman times. The town of Portsmouth itself was founded in 1180 and the first naval dockyard was built there by Richard I during the Hundred Years' War between England and France in the 14th and 15th centuries. Portsmouth's importance for the wars with France resulted repeated attacks by the French in 1338, 1369, 1377 and again 1380.
Despite these continued attacks, nothing was done for the town's defence until 1386, when an earthen rampart was built around the town. Roughly rectangular in shape, this humble mud wall fronted by a ditch defined the form of Portsmouth's fortifications for 500 years.
The first artillery fortifications at Portsmouth were built around 1415. They consisted of two towers, originally built of wood, that controlled the harbour entrance. One was built on The Point at Portsmouth (this tower was later called the Round Tower) and the other was opposite it on Gosport Point. A chain was slung between the two towers at night to close off the harbour entrance. These two points would be the key to the defence of the harbour from this point onwards.
In 1495, the Round Tower was rebuilt in stone and another tower was constructed to the south of it. This new tower, known as the Square Tower, was used first as the governor's residence and later as a powder magazine. Guns were mounted on its roof.
During the reign of King Henry VIII'Portsmouth's fortifications, which were in poor condition, were strengthened again as a reaction to fears of a French invasion.
Around 1522 the earthen walls were repaired and a rectangular coastal battery was built to the south of the Square Tower. This battery became known as the Saluting Platform, since the guns here were used to salute naval vessels entering the harbour.
The Saluting Platform significantly increased the firepower that could be brought to bear on hostile ships approaching the harbour. However, the earthen ramparts had decayed significantly by the 1540s, when a fresh invasion crisis arose.
In 1539 the blockhouse on Gosport Point was replaced with an 8 gun battery and from 1541 to 1545 the walls around Portsmouth were built up in stone. There were three D-shaped artillery towers that flanked the landward walls, and a square tower where the walls reached the sea to the north of the Camber (the inner harbour). To the south, a small fort called Southsea Castle was built in 1544.
However, the new defences were not made with the angular bastions'that were being developed in Europe. The rounded towers had dead ground in front of them, where flanking fire from the adjacent towers could not reach. For this reason, in the 1560s an earthwork bastion (known as Green Bulwark) was constructed in front of the southern flanking tower and a bastion was built at the town gate. On the seafront, the Saluting Platform was rebuilt in stone. The map above shows the Henrican fortifications with these additions.
The next major phase in the fortifications came in the 1580s, when England was again threatened with invasion, this time in the form of the Spanish Armada. This crisis led to the reinforcement of Portsmouth's obselete defences. If the town was to withstand an attack by the soldiers of any well-trained European army it needed to be surrounded by a bastioned trace, which would be capable of resisting modern siege warfare.
The plan above shows a preliminary idea for the fortifications, drawn in 1585. The plan, which is often attributed to Pearse, envisages the enclosure of the town with a full bastioned trace. The old artillery towers are all replaced by bastions, and the Saluting Platform is also shown as a bastion. The bastion flanks are perpendicular to the curtain walls, as was standard in this period.
In the end a similar trace was used, with 5 arrow-headed bastions'(which offered more protection to the guns in the flanks) and a demi-bastion'(where the ramparts met the coast in the north). There was a flooded ditch'in front of the ramparts but there were no outworks.
The main entrance, imaginatively called Town Gate, was made through the flank of a bastion, as was common with 16th century Italianate fortifications (such as Brouage). The Saluting Platform and the Square Tower formed part of the seaward walls but the Round Tower was outside the fortifications, which cut off The Point (it could be accessed via the Point Gate). It is unclear who was responsible for the design of the Elizabethan fortifications built between 1584 and 1586 but Richard Popinjay is a likely candidate.
He was the Surveyor of Fortifications for Portsmouth and had been responsible for rebuilding the Saluting Platform in stone in 1568. It is also possible that he was just one of a number of engineers who contributed to the design.
Because of the huge amount of money that had been spent on the fortification of Berwick-upon-Tweed some years earlier and because the threat of invasion was imminent the ramparts at Portsmouth were built out of earth, which was both quick and cheap.
Although Portsmouth never saw a Spanish or French attack in the 16th century (apart from a naval battle that occurred in the Solent) its defences did see action during the Civil War, when it was captured after a brief siege by the Parliamentarians.
The fortifications themselves however, remained unaltered until the 1660s, when the Anglo-Dutch wars gave rise to new fears of attack. Portsmouth was the most important dockyard on the south coast, and although the fortifications constructed in the 1580s were extensive, they had become obselete by the mid-17th century. In 1662 the Dutch-born engineer Sir Bernard de Gomme'made his first visit.
He became responsible for a major rebuilding of the fortifications, starting with the construction of outworks in front of the Elizabethen defences. This first phase of de Gomme's reinforcement of the fortifications included a covered way'and second ditch.
There was to be a demi-lune'at Town Gate, which then became known as the Landport Gate. De Gomme's plans for the outworks were carried out between 1665 and 1670, but he began a second phase of fortification in the 1670s, when he redesigned the inner Elizabethan bastioned trace with walls revetted in stone.
This work was carried out from 1677 to 1685. The Elizabethan bastions were remodelled (especially Pembroke Bastion which was considered too shallow), but the form of the fortifications remained essentially the same.
Instead of arrow-heads, the bastions had false brays'in the flanks to increase their firepower, and Town Bastion had a cavalier. De Gomme built other fortifications to protect the dockyard at Portsmouth; a battery was built stretching from the Point Gate to the Round Tower and the dockyard itself, which lay to the north of the town, was enclosed by an earthwork bastioned trace.
On the opposite side of the channel de Gomme built a fort on Gosport Point (called Fort Blockhouse) and fortified the town of Gosport with a bastioned trace. To the north of Gosport he built a small fort on Burrow Island, called James Fort. The map to the right shows the area of Portsmouth with de Gomme's fortifications.
In 1701 the War of the Spanish Succession'broke out in Europe and again Britain plunged into a naval conflict with France. Although there was no real threat of an invasion during this time, thought was given to the defences of the rapidly growing town and dockyard of Portsmouth. An engineer called Talbot Edwards drew up a plan for extending the dockyard's fortifications, but in the end his plans were not carried out.
The next major work on the fortifications of Portsmouth spanned the years 1730-1750 and beyond. Colonel Desmaretz carried out extensive work to strengthen the ramparts, but the trace of the fortifications as set down by de Gomme some years earlier was retained.
Desmaretz remodelled de Gomme's bastions and ramparts by adding a continuous false bray at the top of the wall, which gave the garrison's troops a safe place to shoot from at the top of the scarp and three additional demi-lunes were constructed; East Ravelin, Montague's Ravelin and King's Ravelin. The outer ditch was considered superfluous in the face of these improvements and was removed at the same time.
The southern corner of the defences was considered vulnerable, so Desmaretz enlarged the small counterguard'(known as King's Counterguard)that de Gomme had built in front of King's Bastion, extending it eastwards to meet King's Ravelin.
Another reinforcement to this sector of the fortifications made at this time was the Spur Redoubt. Originally a redan'constructed as part of de Gomme's fortifications, this work was rebuilt in stone and transformed into a powerful battery. The guns mounted along the southern face of the Spur Redoubt supported the King's Counterguard but also guarded against enemy ships.
The western curtain wall overlooking the harbour was strengthened with a covered way and the Camber was guarded by the Camber Bastion, which contained a magazine. Desmaretz also extended the fortifications of Gosport.
The defences to the north, which consisted of a small redoubt built by de Gomme, were transformed in 1757 by the construction of the Hilsea Lines, which ran along the entire northern side of Portsea Island (which is in reality a penninsula). Minor reinforcement work continued on the fortifications of Porstmouth itself and in the surrounding area until the end of the Napoleonic Wars. This work included the construction of the Point Battery, a series of casemates placed around the Round Tower and the rebuilding of the top section of the Square Tower to turn it into a semaphore station.
The first part of the 19th century saw more additions to the fortifications, including the construction of a bastioned trace protecting the dockyard. These fortifications, known as the Portsea Lines, extended northwards from the town of Portsmouth. Consisting of four bastions and three demi-lunes, the lines enclosed not only the dockyard but the area called Portsea, where the dockyard workers lived.
In the 1850s and 1860s there were new fears of a French invasion, but by this time the bastioned fortifications of Portsmouth were obselete. A series of outlying polygonal forts were constructed to the north of the town and the Hilsea Lines were strengthened. In the 1870s the walls around Portsmouth were demolished along with the Portsea Lines.
Although the ramparts were mostly demolished in the 1870s, there are some significant remains of Portsmouth's once-impressive fortifications. Along the coast very little demolition took place, since the fortifications there were not inhibiting developement.
This means that the stretch of walls running from the Round Tower to King's Bastion has survived, which includes the 18-gun battery, the Square Tower and the Saluting Platform. All these are in good condition and are well maintained by the authorities. The Round Tower can be visited without charge at any time but the Square Tower is not open to the public.
The Spur Redoubt was demolished and covered by a large concrete sea wall until excavations in the 1990s rediscovered the lower walls, which can now be seen. A modern bridge across the ditch connects the Spur Redoubt with the sally port in the curtain wall near King's Bastion.
The landward fortificatons however, have almost entirely disappeared. The Landport Gate, built in 1760, is the only gate that remains in its original position. King James Gate was built by de Gome in 1687 at The Point and it is now located some distance to the north-east on Burnaby Road.
Portsmouth is easily accessible by train and Portsmouth Harbour station is located very close to the surviving fortifications. Nearby fortified places include Gosport, Southsea Castle and Carisbrooke Castle on the Isle of Wight.