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Valley Works "Rhydymwyn Beyond Top Secret"

A cache by peteb303 Send Message to Owner Message this owner
Hidden : 9/14/2011
1.5 out of 5
1.5 out of 5

Size: Size: micro (micro)

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Geocache Description:

You are looking for a small Micro placed near Valley Works in Rhydymwyn.

Please DO NOT enter the site.
Please DO NOT park near the entrance.

During the 1930's and the threat of war with Germany looming the government decided a facility capable of producing and storing chemical weapons was required. In 1939 after surveying many sites in the area work was started here in Rhydymwyn building one of the UK's most top and best kept secrets, which remained so until it's cover was blown by media interest in the 90's.

The cache might contain a clue to find the bonus cache Valley Works “Woodside”.

The site was soon up and running even though construction was not complete. Several different weapons were made here but Mustard Gas was the main product, and this was made here in two forms Pyro which was the same as the gas used in the First World War and Runcol which was developed later. Pyro had a major disadvantage compared to Runcol. It could not be used at altitude due to it's high freezing point so it could not be dropped form the air. Which was the preferred method of delivery. Runcol became the main product to be produced and this soon became a problem with tunneling of an under ground storage facility not complete. Two above ground sites were chosen for temporary storage. The first was the Antelope site which was where the small industrial estate is now on the opposite side of the where the old railway tracks used to be form Valley Works. The other site Woodside which was a short distance away, you'll need to find the find the bonus cache to discover where Woodside was.

During 1942 Pyro production was now at a stand still but remained ready to start up if chemical weapons were ever used against us. One of the pyro buildings (P6) which was not in use and remained empty became the home of an Ultra Secret Project known as Project X and the building became an Atomic Research Facility. By 1943 there was large scale uranium separation and research into Isotope separation. This was some of the earliest work to be carried out on the development of the Atomic Bomb. This continued until the Americans joined the war, research was then transferred out of Valley and became the Manhattan Project.

After the war chemical production was was halted and Britain now had a new problem. We now had huge stockpile of Chemical Weapons and so did Germany. The government decided that Germany’s weapons would be safer over here out of harms way where couldn't fall into the wrong hands. It's not clear how but they were brought over here and ended up being stored at Valley. They were later processed and graded on site. Depending on the grading it was either burnt or buried in pits of bleach on site. The rest was moved out and put onto ships which where scuttled in the Irish Sea, this was known as operation Sand Castle.

As the site was wound down it was still being maintained and Chemical Weapon production capability remained well into the 50's. Modifications where carried out on site this included reinforcing of the tunnel entrances and the fitting of blast doors. Valley remained in a shroud of mystery as it became a Forward Supply Depot in the Cold War and possibly a Command and Control Centre. There were stock piles of food, medicine, bedding and who knows what else? Just about everything needed to survive a nuclear war. There were secret plans for the tunnels which were Projects Wellbright, Mallard and Trojan. Project Wellbright was the plan to locate the NATO Oil Executive Board (NOEB) at Valley, Project Mallard the storing of the Bank of England gold and Project Trojan the utilisation of the tunnels as a safe haven in the case of nuclear attack.

The locals didn't know much about the place. It was know as ICI or the rubber factory. Back in it's early days it was also known as a Synthetic Rubber factory to help hide it's real purpose. As a kid in the 70's I remember a big green fence and huge nasty guard dogs behind it and in the 80's regular security patrols remained. By this time it was the UK's premier Nuclear Bunker, a bit ironic really being where the Atom bombs development was started. As the Cold War came to an ended and government facility’s were wound down, closed. and sold off. As closed doors where opened, some sites even became visitor attractions such as Furze Hill Nuclear Bunker in Essex. Valley remained a mystery. The site still remains as one of only three government owned and controlled sites in the UK. The full truth about the site will never be known.

After environmental checks a lot of the the site has now been demolished to remove contamination, toxic burial pits have been capped and the site has been returned to nature. Some buildings still remain including (P6). The site is still closed to the public though you can visit by appointment, there is a nature tour and a Historic tour, see the information board near the cache N53° 11.533 W3° 11.508. There is parking near by but please avoid parking in the gateway.

The cache might contain a clue to find the bonus cache Valley Works “Woodside”.

Additional Hints (Decrypt)

Srapr yvar oruvaq Ab.3 Inyyrl

Decryption Key


(letter above equals below, and vice versa)



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Coordinates are in the WGS84 datum

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