Secret Bunker Theories

Wandering around the former site of the stately mansion, one should think not just about what was above, but also about what might have been below. Here are some thoughts about the existence – or not – of an underground bunker somewhere in the grounds of the Battle of Britain House

The most obvious question is whether such a stately home ever had a cellar in its foundation. An early description of Ducks Hill Plantation is referring to the site as a messuage – a house with all the ancillary outbuildings and lands assigned to the same deed. We also know that the farm changed hands soon after the end of World War I, and was improved and expanded. There’s mention and ample evidence of outhouses and sheds, but I haven’t been able to find a mention to a cellar anywhere. However that doesn’t mean it didn’t exist. This may require a search for the architectural plans of the mansion’s expansion. If those plans exist, they would be over a century old… but offer a fascinating insight in the past of the site, and answer so many questions.

Battle of Britain House, Ruislip, UK
The mound is still visible today

It is obvious that the mansion was built on a mound, which can still be seen today. The flat plateau was connected to what used to be the garden via the famous steps. It is not known whether the mound was natural, artificial, or perhaps a bit of both. Could contain a storage area beneath the foundation? There’d certainly be standing space there. But there’s no proof.

Photo of one of the site’s sewer access points

A visual examination of the site of the ruin hasn’t yielded any results. It is still possible to trace the mansion’s foundation, and one can make an educated guess as to where a possible entrance to a cellar might have been. But much of the foundation is covered in thick vegetation and piles of branches so it’s hard to tell. There is a number of concrete trapdoors around the site still visible today. These look like manholes – sewer access hatches. This type of entrance wouldn’t be a convenient access point to a cellar at any case. Please don’t try to open those, they are extremely heavy, and a danger to the many people and animals roaming the woods. I found this one opened a few years back, and managed to shut it, after great effort.

Cold War Bunker ?

Which leads us to the next thought : could there be an underground fortified area, like a bunker, underneath the house, or elsewhere in the grounds? Some local residents I’ve been in contact with subscribe to that theory. They believe that there’s still evidence of an underground installation on the ground, hidden in the woods close to the mansion. This new information emerged in April 2021, and I have been pursuing an expedition to the said locations so it can be further evaluated

Cold War bunker under the Uxbridge Civic Centre © Subterranea Brittanica

The use of the mansion as a training base for secret operatives might have necessitated the creation of such a safe underground space, even if it didn’t exist before. Perhaps an arms or ammo storage, a bomb shelter, or other non-visible fortification would be ideal, to maintain the excellent cover the mansion provided as a base for clandestine operation training. But there’s further – yet informal – evidence, that the Battle of Britain House’s service didn’t cease at the end of the war. The mansion was strategically located close to Northwood HQ, RAF Northolt and RAF Eastcote, and the Royal Air Force played an active role in the mansion’s post-war story. ‘Those who know’ say that intelligence training might have continued into the Cold War… the existence of a possible underground installation from the era could be a theory that merits further investigation. After all, a number of important Cold War civil defense installations existed in the Borough of Hilingdon, in some ‘unexpected’ places – not least the Hillingdon Borough Control under the Uxbridge Civic Centre or the North West Group War HQ in the basement of Hambrough School, Southall

The Tape Relay Room at North West Group HQ, Southall © Subterranea Brittanica

Disclaimer : The main photo diagram of the Cold War installation is from the © Broadway Tower site

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