Until the development of large, long range cannons, military and civil defence activity was mostly carried out on the surface. Combat took place in the open, wherever armies happened to find themselves in proximity, and took the form of skirmishes, charges and close quarter fighting. Towns were fortified with keeps, moats and ramparts where the besieged people spent most of the time awaiting relief from the rigours of isolation and starvation. Underground excavation was limited to dungeons, crypts and cellars, with the occasional sally port for a surprise attack or escape. The attackers occasionally attempted to undermine walls and battlements. Little of this underground activity has left any trace today.
The development of the large cannon, which could batter walls and armies from afar with impunity, must have seemed at first the ultimate weapon. The effect, however, was to send the whole concept of defence below ground, from which it has not emerged since. The design of fortifications underwent radical change with the disappearance of keeps and ramparts, development concentrating on the moat. A substantial ditch was dug up to 60ft deep and 100ft across, which could not be readily filled or bridged. Excavated material was used to build up an inner mound and the lines of approach were levelled to provide a clear arc of fire. The walls of the moat were lined with bricks or masonry, many feet thick, and a network of tunnels installed to enable men to move quickly around the fortification. Firing slits were positioned to create maximum havoc upon the enemy, gun batteries were built and, wherever possible, natural obstacles such as cliffs or hills were incorporated.
Thus protected, an army could sit out a siege, dominate communications and harry the enemy. This remained the situation until 1940 when the fortress at Eben Email fell to a new ultimate weapon – attack from the air. The Kent coast has many such fortifications and they are largely ignored in guidebooks in favour of more visually appealing surface structures. They are, nevertheless, equally impressive in terms of the ingenuity of their construction and their place in military history, even though none were put to the ultimate military test.
Although Dover Castle dominates the town, on the other side of the valley there is a discreet but no less impressive set of fortifications known as the Western Heights. The construction work started in 1779 to counter invasion threats from the French and Dutch, work gathering momentum until 1814 when an armistice was signed. William Cobbett passed this way in 1823 on his ”Rural Rides” and commented ”…a couple of square miles or so were hollowed out like a honeycomb, that either madness the most humiliating, or profligacy the most scandalous, must have been at work here for years”.
Despite such views, work soon began again with the threat of Napoleon Ill and the re-unification of Germany. The major works took place in 1850 and cost £300,000, which included removing the top of the hill and digging four miles of moats up to 60ft deep. The features are a maze of tunnels, cantilevered drawbridges, stairs, wells and firing positions. Although the features were connected by a continuous moat, they formed self-contained units that were capable of fighting on if part of the complex was overrun. The features are the Western Outworks, Citadel, Outer Bastion, North Centre Bastion and Drop Redoubt. The last two are now bisected by a road, for which the ditch has been filled in.
Another interesting feature is the Grand Shaft that was built in 1802 and connects the fortress with an entrance at the base of the cliff off Snargate Street. At the top, 59 steps lead down into a funnel shaped depression where the 20ft wide shaft descends for 100ft. It is brick lined and there are three interlocking but separate spiral staircases, lit by apertures into the shaft. At the bottom, they all converge to join a passage out to the street. it is said that one staircase was for officers and ladies, another for women and the other for soldiers. Obviously Victorian morals decreed that the three types should never meet up on dark stairways! The sites can sometimes be visited by arrangement with Dover Council but the Citadel cannot, being occupied by a Borstal Institution.
The Medway Forts
Following a Dutch raid in 1667, a ring of forts was built around the town to protect the naval dockyard and these were improved and added to during the Napoleonic Wars. Despite the enormous cost, they never saw a shot fired in anger and Chatham today is still dominated by the largest, called Fort Amherst. Of the others, several have been demolished but some still remain, albeit hidden amongst trees or houses. These forts were smaller versions of the Dover fortifications and, although they had underground features, the local rumours of linking tunnels are not true. Fort Bridgewood, Fort Clarence, Fort Pitt and Fort Darland have been demolished although a few features may still be found. Fort Borstal, Fort Horsted, Fort Luton, Twydall Redoubt and Grange Redoubt still remain at the time of writing but permission must be obtained from the respective landowners before visits. The most impressive was Fort Amherst and, luckily for posterity, this has been preserved. It is open to the public and volunteers often dress up in period military uniform.
World War I
This marked a change in the pattern of warfare since the fighting took place in the trenches of France and Belgium, with no requirement for new fortifications in Britain. It did bring in a new development, however, whereby men of the Royal Engineers began to tunnel under the enemy trenches to lay explosive charges, hence the derivation of the word ”mine”. The base depot of the Royal Engineers was at Chatham and the area was used to experiment with new techniques of mining, since the local sand and chalk was almost identical to conditions at the Front. Very few of these trial mines were recorded at the time and, although it is likely that many collapsed subsequently, some still turn up in surprising places. The latest example was discovered following a collapse in a Gillingham back garden in 1988.
During the construction of a roundabout at the junction of the A2 and A278 in Gillingham, a set of 6 galleries was found which had been unsuspected. They were found to be on three levels from 20-50ft below the surface, being dug as a model for mining operations under Hill 60 in France and the subsequent battle at Messines. Each gallery consisted of an entrance tunnel which led to six chambers, each 20ft wide x 30ft long x 7ft high. They were in a very dilapidated condition and had to be completely infilled.
Ramsgate Air Raid Tunnels
The tunnels underneath Ramsgate provided shelter from air raids during the Second World War, a purpose that they had also served the First World War. They consisted primarily of a series of large caves and a disused railway tunnel, that combined could provide shelter for up to 15,000 people.
It was decided to improve this tunnel system at the outbreak of World War II, as people would clearly try to head for the tunnels from a radius of anything up to two miles. A new tunnel was constructed to lessen the distance that people had to cover to get to shelter. A further 11,000 people could find shelter in this new tunnel.
There were originally 23 entrances to the tunnel complex, with smaller spur tunnels connecting to the main tunnel. Each entrance was fitted with a heavy steel gas proof door. The idea was to close a gas door only in the immediate vicinity of a gas bomb detonation. The remaining gas doors were to be kept open, unless their immediately surrounding area was also contaminated with gas. It was hoped that by keeping doors open in one area of the town, fresh air could still be drawn in from areas not contaminated. It was considered to be highly unlikely that the whole area would be contaminated at any one time. Ventilation in any other circumstance was provided by ten air vents that ran the length of the main tunnel.
Toilets were constructed by cutting recesses into the chalk walls, with the gents’ on one side and ladies on the other. Each recess had two chemical closets. Corrugated asbestos cement partitions and doors were used to try and make cleaning these toilets an easier task……
There were also first aid posts dotted throughout the tunnel, again lined with asbestos. These posts had hot and cold water supplies, a sink and a couch.
Light in the tunnel was provided by a small generating plant that ran on petrol, with a battery set that could provide power for 10 hours should the generator break down. The battery rooms were situated near ventilation shafts to vent the exhaust fumes out of the tunnel.
Blaw Knox Tunnels
These tunnels were constructed as an extension to the existing factory in 1941. Building above ground was considered imprudent due to the vulnerability of the Medway estuary to air attacks. The two tunnels that housed the factory workshop area were both 100m long, and were linked by four traversing tunnels of slightly shorter length.
The Shorts Brothers also constructed a large system of air raid shelter tunnels, which comprised of two main tunnels some 300m long, traversed by 14 smaller connecting tunnels. The shelter tunnel complex was connected to the factory complex via a single tunnel approximately 400m long.