Sheerness stands at a point on the east bank of the river Medway, where it flows into the Thames estuary. This strategic location was first fortified in the 16th century, when Henry VIII'had a blockhouse'built there, one of three built on the Isle of Sheppey to augment the system of five blockhouses that were built elsewhere on the banks of the Thames in 1539.

The 1666 plan for a fort at Sheerness, showing the existing Henrican blockhouse and an enclosing earthwork battery, with the proposed improvements drawn in lighter lines.

It consisted of a square tower, which probably mounted artillery, surrounded by an earthwork battery where more guns were mounted. The focus of the firepower was over the river confluence, but the earthworks also extended round the landward side of the tower.

In 1665 preparations were made for turning the humble blockhouse at Sheerness into a dockyard suitable for repairing naval ships to supplement the substantial dockyard further up the river Medway at Chatham. In 1666 the engineer Sir Bernard de Gomme'was sent to Sheerness to review the fortifications. He designed a simple square bastioned'fort to enclose and strengthen the existing blockhouse and earthworks.

In 1667, the Dutch fleet sailed up the Medway, landing troops to capture the unfinished fort at Sheerness on the way. The Dutch took supplies, ammunition and guns, then burned everything that was combustible and moved upriver to attack the fleet at Chatham.

A painting of the Dutch in the Medway by Schellinks. The burning fort at Sheerness is shown at the bottom left.

Following the destruction caused by the Dutch raid, the fortifications at Sheerness were remodelled according to new plans drawn up by de Gomme, which may date from before the raid, but cannot have progressed very far by that stage.

The new plan for the fortifications of Sheerness, this time enclosing the dockyard with a strong landward front.

The new plan consisted of cutting off the point with a strong landward front with a flooded ditch'and enclosing the dockyard to the north. The old 16th century square tower was retained and formed the northern end of this enclosure. Just to the north of the tower was a wide semi-circular battery, which covered the river confluence and could bring its guns to bear on any ship sailing up or down the Thames.

The docks themselves were sited on the western side of the dockyard (on the Medway). This side of the dockyard was protected by a bastioned front with the main gate to the dockyard at its centre. The eastern side of the fortifications were less vulnerable, being hard up against the shore, so they were protected by an indented line running up from the land front towards the tower.

The landward front consisted of two demi-bastions'(named Queenborough and Minster) and a demi-lune, with a covered way'beyond the ditch. There was a gate in the centre of the curtain of the landward front, with bridges leading across the ditch via the demi-lune.

The remains of the indented lines along the eastern side of the fort. The lower parts of the walls are now covered by shingle.

Given the Dutch attack of 1667, the construction of fortifications was directed with considerable urgency. In order to be made defensible as soon as possible, the ramparts were at first unrevetted earthworks, but were later revetted in stone. Work slowed down after the threat of attack subsided, and the fortifications were only completed in 1685.

Sheerness with the new 18th century landward front (the Sheerness Lines) protecting Blue Town.

The dockyard expanded throughout the 18th century, its primary work being the minor refitting of ships operating in the North Sea, but some shipbuidling was carried out (frigates'and some fourth rate ships of the line'were built at Sheerness during this period). The workers at the dockyard lived outside the fortifications in simple wooden cabins painted with naval blue paint.

This area, known as Blue Town because of the colour of these houses, was enclosed by an earthwork bastioned trace at the end of the 18th century amid growing fears of a French invasion. In addition to this, a straight defensive canal was dug farther to the south in 1782, stretching from the Medway to the Thames, about 2 miles (3.2km) in length.

There was a flooded ditch, but initially no demi-lunes or covered way. These defences resembled those of fortified towns in the Netherlands, which is hardly surprising given the wet nature of the low-lying terrain on the Isle of Sheppey.

The left flank of a bastion in the Sheerness lines.

In 1797 Sheerness witnessed the Nore Mutiny, during which the crews of some 28 Royal Navy vessels lying off Sheerness took control of their ships and made demands for better pay and the end of the war against France. When their demands were refused, the mutineers blockaded London and there were fears that they would attack Sheerness.

View of a tenaille in the early 19th century fortifications linking de Gomme's indented lines with the Sheerness Lines.

The garrison was reinforced to 3,000 men and the shot was kept heated for the guns on the battery. Eventually the mutiny was subdued with little violence and the ringleaders were hanged, but even by the few shots that it fired, the battery at Sheerness proved its usefulness.

The Napoleonic Wars saw new fears of French invasion, which led to improvements to the fortifications at Sheerness. The lines constructed in the late 18th century to protect Blue Town were extended along the eastern side with the construction of a narrow bastioned trace running up the coast to meet the indented lines of de Gomme's fort.

Interestingly, this trace along the riverbank used Vauban-style tenailles, although these were not used on the landward front. A demi-lune was constructed in the ditch of the landward front to protect the entrance. This demi-lune was later strengthened by a loopholed'brick wall.

Map of Sheerness in 1861, showing the early 19th century fortifications, which had already been outgrown by the dockyard and town. By this time de Gomme's inner landward front had disappeared.

In the 1820s there was a large fire at Sheerness, which coincided with a redesign of the dockyard. It was probably around this time that the remains of the land front and western side of de Gomme's fort were demolished in order to accommodate the enlarged dockyard.

Map of Sheerness in 1911, showing the remains of the 19th century fortifications, the location of Garrison Point Fort (top left) and part the Queenborough lines (bottom right).

In the 1860s the fortifications were again revamped, primarily with the construction of a large new battery, known as Garrison Point Fort, on the site of the henrican tower. The fort took the form of a large semi-circular stone construction with casemates'for 36 rifle muzzled loaded guns.

The canal to the south that had ben dug in 1782 was expanded to become the Queenborough Lines, with a 6-gun battery at either end (Barton's Point Battery in the east and West Minster Battery in the west). The ramparts along the eastern side of the dockyard were the site of new gun emplacements in the 19th century and anti-aircraft batteries in the Second World War.

Visiting Sheerness

The navy dockyard was closed in 1960 and is now used by the Medway Port Authority as a commercial port. Today, the henrican blockhouse that represented the humble beginnings of Sheerness is long gone and any remains would be buried under Garrison Point Fort.

The remains of the loopholed wall inside the demi-lune in the Sheerness Lines.

Of de Gomme's 17th century fort, only the indented lines along the eastern side remain, and these are in poor condition. The portland stone has been patched up with brick and most of the walls are buried beneath the shingle that has built up on the beach.

The base of sentry post at an angle in the indented lines.

The bases of two sentry posts'have survived along the lines - the only surviving examples of this design, which was also used at Plymouth citadel. About halfway along the indented lines, the Medway Port Authority has made a barrier out of large rocks and barbed wire.

This barrier prevents public access to the northern half of the indented lies and Garrison Point Fort, as well as possibly having caused damage to the 17th century wall by piled large rocks against it.

It would be nice to see the scant remains of de Gomme's fortifications treated with a little more care and respect, but as with other less well-known fortifications such as Cockham Wood Fort, they are allowed to decay into obscurity.

A flank in the indented lines. The barrier of rocks can be seen on the right.

The earthwork bastioned trace running south from de Gomme's indented lines has been partially preserved, the flooded ditch protected by a modern concrete sea wall.

The ramparts to the south of the indented lines, with Second World War searchlight towers in the background.

Of the Sheerness Lines, only the two half-bastions either side of the entrance road and part of the brick loopholed wall in the demi-lune survive. The Queenborough Lines mostly survive in the form of a wide water-filled ditch and earthwork bank, but the two batteries are gone.

Sheerness has a station with regular services running from Sittingbourne, where there are trains to and from London. Apart from the few remains of the fortifications, there is little of interest to the visitor.

Condition Access to fortifications Size of fortress Accessability of town Museum/Info Overall score
3 4 4 7 1 3.8
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