Summary
Shornemead Fort, a coastal defence constructed under the Royal Commission between 1861 and 1871 to defend the Thames Estuary. It is built on the site of a battery of 1795 and a polygonal fort built between 1847 and 1853. The fort was partially demolished in the 1960s.
Reasons for Designation
Shornemead Fort, rebuilt between 1861 and 1871 as part of the Royal Commission coastal fortifications, is scheduled for the following principal reasons:
* Historic importance: as part of the massive programme of defensive works stemming from the 1860 Royal Commission prompted by fears of a French invasion; built on the site of two previous batteries/forts forming part of the defences of the Thames Estuary;
* Architectural importance: it provides a good example of the construction and form of a mid-C19 casemated fort;
* Documentation: the site is well documented including committee reports, historic plans, maps and photographs, as well as recent archaeological assessments;
* Potential: for archaeological deposits associated with the construction and use of the fort and possibly its predecessors. Additional, below-ground structures, apart from the well-surviving magazines and shell stores, may survive below the demolished fortified barracks and the infantry caponiers in the infilled ditch;
* Group value: with the other designated fortifications associated with the defence of the River Thames including Coalhouse, Cliffe, Tilbury and New Tavern Forts.
History
The Royal Commission fortifications are a group of related sites established in response to the 1859 Royal Commission report on the defence of the United Kingdom. There were eventually some 70 forts and batteries in England which were due wholly or in part to the Royal Commission. These constitute a well-defined group with common design characteristics, armament and defensive provisions. Whether reused or not during the C20, they are the most visible core of Britain's coastal defence systems and are known colloquially as `Palmerston's follies' after Lord Palmerston (1784-1865) who was Prime Minister at the time.
A battery on the site of the current Shornemead Fort was first constructed in 1795, following the outbreak of war with Revolutionary France, as one of three batteries to better defend the Thames Estuary from attack (the others were at Coalhouse on the Essex side and Lower Hope, 5km downstream from Shornemead. The batteries were all semi-circular in plan with a revetted earthen rampart for 24-pounder guns on traversing platforms (four at Shornemead) with magazines and barracks at the rear enclosed within a triangular rear wall. The battery was surrounded by a waterfilled defensive ditch. Following the long peace after Waterloo the battery was not maintained but remained extant until renewed fears of a potential French invasion led to the construction of a new battery between 1847 and 1853. Based on the latest German fortification designs, this was the first ‘polygonal’ fort to be built in Britain. Pentagonal in plan, it consisted of three sides with open gun positions for thirteen smooth-bore 32-pounder guns mounted on traversing platforms, with defensible barracks and service buildings forming the rear two sides. A pair of brick musketry caponiers in the ditch provided close protection from infantry attack and the corners of the barrack range projected as demi-bastions to protect the entrance to the fort. A bomb-proof magazine and artillery store were placed behind the ramparts. The new battery, which had suffered from serious foundation problems, was to have a short life. In 1859, as a result on renewed fears of a French invasion caused by the enlargement of the French Navy and improvements in artillery, the Royal Commission on the Defences of the United Kingdom under Lord Palmerston, recommended the strengthening of Britain’s coastal fortifications, particularly those protecting the naval dockyards. The Commission recommended that the Thames Estuary be defended by a triangle of forts by rebuilding the existing forts at Coalhouse, East Tilbury in Essex and Shornemead and adding a new fort at Cliffe in Kent. Tilbury Fort and New Tavern Fort at Gravesend were re-armed and later remodelled (from 1868) to provide an inner defence.
At Shornemead, new land had to be purchased for the larger new fort and work began in 1861 with the demolition of the existing fort. The trace (outline) of the fort was a curved face with, as before, the rear two sides formed by defensible barracks, faced in Kentish ragstone, either side of the entrance to the fort. A granite-clad exterior wall protected the concrete-roofed brick casemates with gun embrasures protected by iron armoured shields. The arc of casemates was armed with eleven 11- inch RMLS (rifled muzzle-loading guns) with an open battery of three 9-inch RMLS adjoining the casemated battery at the up-river end. Arched brick magazines, with storage chambers alternately for shells and cartridges, were provided in a basement under the casemates and open battery with lift shafts to raise the ammunition to the guns. The magazines were protected on the parade ground elevation by an earthen bank against the rear wall of the casemates. Because of the unstable nature of the ground a thick raft of concrete, with associated deep piling, was laid beneath the casemates, open battery and the magazines. The casemates and open battery were fronted by a deep ditch into which projected three infantry caponiers, reached from the ammunition passage of the magazines. Beyond the counterscarp the ground was sloped into a glacis terminating near the river’s edge.
The barracks were partly built on the foundations of the 1852 fort, with the outer windows mounted with steel shutters with musketry loops. The enclosed parade ground contained several structures including two brick gyn (lifting tripods) and tackle stores with tiled roofs.
A mine depot for mining the river during wartime was established in 1878 immediately to the west of the fort with various storage buildings. Supplies for the fort were mainly brought by river and a timber jetty with a stone causeway was built in front of the fort in 1877.
The construction of the new fort was completed around 1870-1871 and was supervised between 1865 and 1871 by Lt Colonel Charles Gordon (later famous as Gordon of Khartoum).
By the 1880s advances in naval artillery technology, particularly the development of more destructive high explosive shells, meant that the fort was modified around the end of the 1880s or early-1890s to provide greater protection. The ditch was infilled to provide a thicker barrier to enemy fire and a sloping thick concrete apron was laid in front of the sill of each gunport. However, despite these modifications, by the turn of the C20 the range of the fort’s armament of RML guns was outstripped by that of more powerful rapid-firing, breech-loading naval guns. Shornemead’s armament was removed in favour of sites for breech-loaded guns at the other Thames forts as Shornemead no longer had sufficient command of the river to justify its rearmament. A small battery of two 6pdr quick-firing (QF) guns for local defence was built on a mound 100m east of the fort by 1895 and by 1901-2 a supporting pair of searchlights in concrete emplacements were installed at the river’s edge some 80m to the north-west of the fort. A submarine mining establishment was constructed immediately west of the fort to operate a minefield in the river. This was completed in 1878 and eventually included mine and equipment stores, lecture rooms and tramways and turntables connecting with a pier provided with cranes for lifting mines onto minelayers.
During the First World War the fort was used for submarine mine warfare courses but was not rearmed. After the war the fort was mainly used as accommodation for musketry couses on the nearby Milton range. During the Second World War, a brick and concrete casemated gun house was built over the detached QF battery. This anti-invasion battery housed two ex-naval 5.5 inch breech-loading guns and was protected by two pillboxes let into the river wall. In 1944, for Operation Overlord, a concrete landing craft hard was built on the river’s edge in front of the fort, largely destroying the Victorian causeway.
At the end of the Second World War, the fort was allowed to fall into decay. Starting from around 1960, much of the fort was destroyed by a programme of explosive demolitions undertaken by the army for training purposes. The barracks and the inner face of the casemates and open battery were destroyed. The Second World War anti-invasion battery was demolished during the 1970s but the two pillboxes and the landing craft hard survived. An earthern flood defence wall was built in front of the fort. In 2000 the fort passed into the ownership of the Royal Society for the Protection of Birds (RSPB).
Details
PRINCIPAL ELEMENTS: the site comprises the surviving above-ground casemates and the open battery at their south-west end, forming a curve about 158.5m on the seaward face and protected by a (now infilled) ditch, along with their below-ground magazines. To the south of the casemates, and north of the access road, is an open area comprising the parade ground and the potential below-ground remains of the demolished fortified barracks that formed the southern boundary of the fort.
DESCRIPTION: the casemates and open battery have a curved plan, facing north and west with a short straight return to the east. The casemated gun emplacements are of stock brick with a topping of thick mass concrete and faced on the seaward side with granite blocks, except at the western end where it is clad in concrete cast to resemble granite blocks. The eastern return wall is of rusticated ragstone blocks and has a window with a brick segment arch. Adjoining it to the east is a concrete base with a southern brick retaining wall. This was a later coal yard present by 1926. The south return of the casemates has an infantry loophole with a York stone sill and lintel. The interior face of the casemate range and the rear part of the vaults of the eleven casemates have been demolished leaving the surviving remains of the vaults exposed. The three easternmost and two westernmost casemates retain part of the brick vaulting but the rest have only the thick stone blocks to the arch over the embrasures surviving. The arched iron blast shields to the embrasures of all the casemates survive, as do the stone blocks of the canted front walls. These are largely covered with modern graffiti. The blast shields all retain the pair of vertical iron columns, with revolving metal reels, for attaching the rope mantlets that protected the interior of the emplacement from debris if the shields were hit by enemy fire (the easternmost casemate has only one of the pair). The iron racer tracks for traversing the guns survive to most of the casemates along with the remains of other iron fittings such as overhead loops for raising the guns off their carriages.
On the seaward side the embrasures, topped by segmental relieving arches of large rounded granite blocks, are separated from each other by curved projecting piers. In front of the embrasures are sloping semi-circular concrete aprons, added in the late-C19 after the ditch was infilled. Flanking each gun embrasure are steel grills set vertically, possibly smoke vent outlets. The roof has a slight overhang. On top of the casements, at either end, are the remains of two observation posts. At the western end, this is a roofless brick structure in a semi-circular pit sunk into the concrete roof of the casemates. It possibly relates to the submarine mining establishment but its date is unclear. At the eastern end, the observation post is a rectangular building with a reinforced concrete base and brick walls which have mostly been lost to army demolition. The damaged concrete roof survives but now rests forward of its original position. This observation post probably relates to the Second World War 5.5inch gun position to the east of the fort. On the north eastern end of the roof is a hexagonal concrete platform with bolts for a light gun mounting.
West of the casemates, the three open gun emplacements are of brick topped with mass concrete, with granite sills to the widely-splayed embrasures. The seaward face is largely obscured by a later earth mound but consists of granite blocks. The gun positions retain their racer tracks. At the north end of the battery is a brick-vaulted ammunition passage. At the end of the passage is a recess with a stone lintel containing a ringbolt for an ammunition lift. The southern side wall of the battery survives but the massive rear wall with a concrete core and brick facing has been partly demolished. Abutting the southern end of the rear wall and facing east are the vestigial remains of the defensive barrack block with an arched entrance to a passage into the battery on its upper floor.
The brick-vaulted basement which extends continuously below both the casemates and the open battery casemates, is sealed off and partially flooded but a survey in 2022 showed that it survives in good condition. It consists of alternating shell and cartridge stores for each gun position, accessed from an ammunition passage running along the seaward side of the fort with a lighting passage running along the parade ground side with hatches to light the ammunition stores. These have stone lintels and sills. Vertical circular shafts for the shell hoists survive as do some of the metal winches. There are blocked passages which gave access to the three infantry caponiers in the ditch and blocked entrances to the basement rooms under the demolished eastern barracks. Some iron fittings and timber door frames survive in the magazines and passages. The whitewashed brick surfaces contain a good deal of historical graffiti dating from all periods of the fort’s occupation and there is stencilled signage indicating the numbers of the magazines.
The rear of the casemates and open battery are abutted by an earthern ramp, partly containing rubble from the demolished inner face of the casemates but originally added in the late 1880s, sloping down to the parade ground and site of the demolished fortified barracks which formed the rear of the fort. Little remains above ground but remains of the fortified barracks and structures on the parade ground relating to the 1840s battery may survive below ground. This area is bounded by the C20 concrete access road.
The ditch in front of the fort has been infilled but buried evidence of the three infantry caponiers may still survive.
EXTENT OF SCHEDULING: The scheduling aims to protect the trace of the above and below ground structures of the casemates and open battery, the area of the demolished fortified barracks and the parade ground (as far as the access road to the south of the site) and the infilled ditch on the seaward side of the fort (to a depth of 10m from the face of the structure).
EXCLUSIONS: The large concrete ‘Lego’ blocks, which have been positioned to prevent access to the basements, are excluded from the scheduling, although the ground beneath them is included.
