Dean Hill and the Defence Munitions store 

Naval Munitions

Nuclear Munitions

Decommissioning the Site

D Day Preparations

Lockerley Mechanicals


rnad aer 01tnThe 243 Ha site of the former Royal Navy Armament Depot (RNAD) is located at Dean Hill on the border of Hampshire and Wiltshire. It is now known as Dean Park and is home to a number of small enterprises. It operated between 1941 and 2004 as a munitions storage and maintenance facility initially for the Royal Navy but, in later times, for all branches of the Armed Forces.

 

ddayaerial01 tnWork began on the site in 1938 prior to the outbreak of WWII and it was opened operationally as RNAD Dean Hill in 1941. At the time a number of footpaths were closed off.  The border betwixt Hampshire and Wiltshire runs through the edge of the area (as it does indeed run through the building hitherto known as the Red Lion - it ran between the public and saloon bar - a signficant issue when closing times differed in each county). Those paths within Wiltshire were formally closed and recorded as such. Those in Hampshire were not formally closed and, as identifed above in the article on boundaries, a footpath is for ever. As a consequence recent attention has been focused on re-establishing the rights of unimpeded access to the footpaths and, at the time of writing in 2017, the proposal has been the subject of an appeal but the desire to see these paths re-established remains strong. The attempt to have these footpaths reinstated on the Definitive Map was rejected by the inspector in 2018  - a cash strapped county council being no competition against well funded  legal resources perhaps.  Go to Top

Naval Munitions

A wide variety of naval munitions was kept there before being transported by rail to the forward coastal RNAD locations at Frater in Gosport and Priddy's Hard where they were loaded onto navy vessels for active service. The depot was connected to the main Salisbury to Southampton railway line by a standard gauge railway via a large marshalling yard at the east side of the depot. Munitions were stored in a series of 24 underground magazines cut into the chalk hillside. The magazines were formed of short tunnels built in a curve such that, should there be any accident, any blast might be better contained and would be deflected by berms.
An internal narrow gauge - 715mm based on bronze rails - linked the magazines to the workshops. The workshops, together with a network of laboratories, were responsible for the refurbishment of the weapons they contained and they were heavily protected and reinforced.  Go to Top

Nuclear Munitions

Contrary to popular belief, nuclear weapons were stored there only on a very temporary basis - often little more than overnight. Nuclear weapons were transported by road in large lorries from the Atomic Weapons Establishments at Aldermaston and Burghfield near Reading. The associated nuclear materials wre transported from Ministry of Defence reactors at Chapelcross and Calder Hall in convoys supported by detachments of marine commandos and supported by fire service appliances and motor cycle out-riders from the Special Escort Group of the Ministry of Defence Police.
Nuclear weapons were stored in the specially reinforced number 1 magazine and the detachment of Royal Marines were accommodated on their own specially defended block - the number 37 building. The depot and its nuclear associations came to public attention in January 1987 when a lorry containing nuclear weapons skidded off the road on ice near the west gate. How journalists came to hear of it is interesting - this was the era well before mobile phones - but the news was suppressed by what were known as D Notices and the stroy only lives on in local tales. D Notices were a form of government censorship and they would be hard to implement in the era of Twitter, FaceBook, InstaGram and email.

Throughout the existence of the depot security and crime prevention was provided by its own police detachment of officers from the Ministry of Defence Police. Prior to 1971 this force had been known as the Admiralty Department Constabulary and the Royal Marines Police.

Decommissioning the Site

In 1988 the rail connection to the main line was discontinued. In 1991 RNAD Dean Hill was renamed DM (Defence Munitions) Dean Hill. The entire rail installation, including that of the marshalling yard, was removed in 1994. Following a study by the DM Rationalisation Study team the decision was taken to close the site and its activities were moved to other defence munitions establishments across the UK. DM Dean Hill finally lowered the Defence Munitions and Union flags at the main gate during a sunset ceremony on 31 March 2004.  Go to Top

Lockerley and D Day Preparations

Lockerley was the site of some 15 miles of sidings and a large camp of canadian and american service men. Little evidence of this remains; even the airstrip is not mentioned in a review of the WWII airstrips in Hampshire. After the D Day landings the site was restored, very roughly, to agricultural use. In fact so roughly that it can not be used for other than grazing deer. There are some aerial photos of this period and of this area on www.woodleynet.co.uk and a visitor should easily be able to match some of the buildings shown with those extant. One image is the intriguing image of Spring Cottage public house and this too has been identified; it's now a private house in East Grimstead. The area has a number of pill boxes many of which surround the armaments depot at West Dean. Older Ordnance Survey maps showed no detail relating to the depot - indeed, they showed the footpaths and field boundaries of an earlier era.  Go to Top

Lockerley Mechanicals

The Lockerley Mechanicals have undertaken a long term project to research this recent but forgotten period. At a recent meeting LIDAR plots of the area of the sidings were shown. LIDAR plots are colour plots which show the subtle changes in land height which can arise due to ancient land use. The LIDAR technology has a resolution of the order of 100mm and it will show the underlying topology of an area independently of existing vegetation and, to a degree, current use. One feature noted in the small area that was shown was the presence of a pathway leading from the site of an early stone age settlement across Critchells Green.

If you would like to add to our knowledge of this period contact the Lockerley Mechanicals or the site admin.
The depot at Dean Hill will have been in extensive use in the 1943 – 1944 period as a US Army stores and comprised some 15 miles of rail sidings and some 24 weapons storage tunnels. The Royal Observer Corps were stationed in the area during this time as was a Canadian Corps and the foundations of their barracks can still be seen. For a short while the depot at West Dean was used to store nuclear weapons in transit. One notable occasion being a very frosty Sunday in 1987 when one of the delivery convoy slipped off the road. The press was restricted from reporting the incident. There was even a full size airstrip in the grounds of Lockerley Hall though no trace of this is apparent and it is not referenced in the review of airstrips in use in Hampshire during WW II.  Go to Top