Fan Bay Deep Shelter

Fan Bay Deep Shelter

Fan Bay Deep Shelter is a system of underground tunnels located on the edge of Fan Hole on the White Cliffs. The shelter is located on the land which was purchased in the national appeal to buy the remaining section of the White Cliffs in 2012. The tunnels are in excellent condition and today remain the biggest and best preserved deep shelter in the Dover area. The underground tunnel system is almost all that remains of the Fan Bay battery. The site is an important part of UK conflict archaeology and it is made even more unique because two sound mirrors were located alongside the lower entrances. Part of the project seeks to uncover these mirrors, the survival of which would make the site nationally significant.

The National Trust local team supported by volunteers is in the process of excavating with the eventual aim of opening the Fan Bay tunnels to the public. This will involve the excavation of all three entrances and stabilization work to the underground structure. The National Trust is seeking to open the tunnels to the public by guided, torch lit tours hopefully in mid 2015. It is envisaged that very little work will be done to the inside of the tunnel system so visitors can enjoy a raw and truly unique historical experience.

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A typical section inside Fan Bay Deep Shelter

A historical summary of Fan Bay Battery:

The 2nd of September 1940 was a dark day for the town of Dover when for the first time it was the target for German guns now sited on the French Coast. Shells were just 60 seconds flying time from the town and over the following years of war many civilians and servicemen and women would lose their lives to German shells. The Germans had not been idle since the end of the Battle of France and had built large gun batteries in the area of Cap Blanc Nez and Cap Gris Nez, part of the so called Atlantic Wall, which would be used to support the planned invasion of England, Operation Sealion as well as for shelling the coastal area around Dover.

Following the Allied evacuation from Dunkirk, Churchill was infuriated to discover German shipping moved freely in the Dover Strait and with an increasing risk of invasion the War Office met in early September 1940 and approved sites for gun batteries along the most likely area for invasion. Churchill had also given orders that gun batteries should be able to hamper the movement of enemy shipping along the French coast. Fan Bay, along with other batteries to the east and west of Dover made up the ’Fortress’, a crucial part of the UK’s Second World War armaments and would be the first line of defence in case of invasion. To take the fight to the enemy Wanstone Battery was equipped with two 15 inch guns, named Winne and Pooh and along with the large railway guns were the only offensive weaponry out of all of the Dover fortifications, the others being designed for short range defensive purposes.

Construction of Fan Bay Battery began in November 1940 and its three six inch guns were installed by the end of that month. Weather hampered construction through winter of 1940/41 but eventually it was brought into action and the battery fired its first proving rounds on the 28th February 1941. The Battery was manned by 122 officers and other ranks from the 203rd Coast Battery, Royal Artillery, in due course 180 Army personal would be stationed here. When the South Foreland, Fan Bay and Wanstone Farm came under a unified command they became the 540 Coast Regiment. The finished battery had three six inch guns, magazines, radar, plotting rooms and large accommodation blocks both above and below ground (see fig: 1). Next to the lower tunnel entrances, known as drift tunnels were two sound mirrors and were relics of the previous war. The hastily constructed fortification represented cutting edge technology in its day and was personally inspected by Churchill, leading Generals and the American Secretary of State for defence.

The battery also had a large ‘deep shelter’ where troops could take refuge during counter bombardments. Designed to shelter 190 people, the deep shelter was carved out of the chalk by personnel from the 172nd Tunneling Company, Royal Engineers and was reached by one of three entrances. The shelter was constructed by driving through the chalk and then supporting that with reinforced heavy duty Iron girders and metal sheeting. Work commenced on the 20th November 1940 and was complete and handed over on the 28th February 1941, just 100 days of construction. The total floor space of the 6 chambers is 3500 square feet and located at an average depth of 70 feet (21 meters). When the shelter was completed it could accommodate all of the military personnel, with two tier bunks which had spaces between for rifle racks, stores and even a hospital. To enable the spoil to be removed from the tunneling a small narrow gauge railway was constructed allowing hand operated trucks to take the spoil to the cliff edge where it was tipped over. Fan Bay was unique in being the largest deep shelter and the drift tunnels accessed the two Sound Mirrors on the side of Fan Hole (see Fig:2).

Sound mirrors came in a variety of shapes and sizes. One of these features at Fan Bay dates back to the First World War when it was used in conjunction with a Sound Mirror at Joss Bay, North Foreland and provided early warning of enemy aircraft approaching London. From the outbreak of the First World War and up to the late 1930’s the Air Ministry experimented with some degree of success in building a chain of these listening devices to give early warning of aircraft approaching the United Kingdom. Even though these devices had proved themselves in wartime, technology never stands still and Sir Robert Watson-Watt was bringing to fruition a means of early warning using radio waves, what we call radar today. However these devices were not destroyed and indeed did play a small role in the Air Defence of Great Britain in World War 2 when the Luftwaffe paid particular attention to the radar stations that had been built around the coast. What is unique about the Fan Bay Sound Mirrors is the material condition they are in and it is a stated aim of the project to conserve the two sound mirrors at site.

The gun batteries and land remained under military administration until the 1960s, after which the land was returned to their original owners, however this land now had redundant gun batteries sited on it. In the 1970’s a local campaign started to ‘rid the White Cliffs of the eyesores of war’ in which Fan Bay along with other military structures throughout the Dover area were demolished. In Fan Bay only the subterranean features survived and the deep shelter, plotting rooms and magazines had their entrances covered over. Fan Bay had three small brick entrance blocks protecting the entrance to the shelters, when these were demolished they were toppled inwards which protected the main structure of the shelter. It is believed that the sound mirrors that were constructed into the side of the hill side were covered over and after a small preliminary excavation both mirrors have been confirmed to survive and indeed seem to be in remarkable condition.

One of the entrances into Fan Bay become accessible again in the 1980’s but the remote location of the site, combined with the fact that the entrance was extremely difficult to locate, helped preserve the site and has meant that only a few local historians and cavers have visited the tunnels.

What Work has been done so far?

Considerable work has taken place since the National Trust purchased the land around Fan Bay in 2012. NT have been working with a local group called KURG (Kent Underground Research Group). They have compiled a new scale survey of the tunnel network, as well as a report on the condition of the tunnels, as well as a graffiti survey and photographic survey also compiled by the Group. The National Trust then commissioned as asbestos report which found minimal contamination underground. This asbestos has now been removed and air quality tests have confirmed the air is safe to begin work.

With the asbestos removed a full structural survey was undertaken and the tunnels were found to be in good condition with no major structural issues. A second structural and geological survey has also been completed and found the tunnels to be safe apart from a few unlined areas of tunnels on the stairs and the sea ward tunnel. These sections will be supported and finished in wood by mine engineers to match the original wooded supports of the 1940’s.

A secure entrance was put on the shelter in September 2013 to protect the public and allow equipment to be left in the tunnels in between work days. The spoil blocking the Stairway from the surface to the underground tunnels has been removed and the process of removing the entrance spoil from the top set of stairs was commenced and completed by the KURG on the last work day of October 2013. With this work complete it was at last safe for the National Trust to allow volunteers and contractors into the tunnels to begin work.

What work needs to be done:

Fan Bay is located in an AONB (Area of Outstanding Natural Beauty), SAC (Special Area of Conservation) and SSSI (Special Site of Scientific Interest). Doing any work in the area must be carefully planned to minimise damage to the chalk grassland. The local property team began a detailed planning application over the winter months and when this application approved we hope to begin surface work some time in 2014. The planning application will need to carry out a detailed biodiversity assessment, archaeological investigation and must show how we will limit or repair any damage to the chalk grassland on the surface.

Whilst we compile the planning application there is all sorts of work which the National Trust volunteers and other contractors have been doing to the inside of the tunnels which includes securing and clearing the underground entrances, stabilising some sections of the tunnels, cleaning and reinstating the internal ductwork. Two new doors have been constructed and installed to protect the lower entrances when they are exposed. Over the course of many working days Volunteers lead by National Trust staff have been at work in the tunnels. One estimate puts the amount of spoil that has been dug and bagged for disposal as sixty tonnes but in addition to this much more has been moved within the tunnels making good some areas and also to cordon off an area of the tunnels that is has been identified as unstable.

When the planning application is approved work will begin to excavate and reinstate the original entrances on the site. Once these entrances have been opened and secured, further improvements and clearing works will be done and it should not be long now before Dover has another very important Conflict Heritage site open to the public. All of this would not be possible without the dedicated work the volunteers have put in at Fan Bay and there is further opportunity for people to get involved with getting the site ready, as well as helping to research the historical background.

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Fig: 1. Plan of Fan Bay Battery, surface and subterranean 1943

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Fig:2 Plan of the underground workings at Fan Bay.

Contact:

For further information or enquires please contact Jon Barker who is coordinating the project.

Jon Barker
Assistant Visitor Experience Manager
South Foreland Lighthouse
The Front
St Margarets Bay
Dover
Kent
CT156HP

Email: jon.barker@nationaltrust.org.uk
Office: 01304 853281
Mobile: 07500782943