Rhydymwyn Valley

RHYDYMWYN VALLEY HISTORY SOCIETY

 

Nant Alyn Road, Rhydymwyn, Mold, CH7 5HQ​

Tunnel Tour Season 2026

Tunnel Tours in 2026​

The Rhydymwyn Site is now open again.

 

Access

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The latest update that we have from DEFRA is that the full site is now accessible with the exception of the Bird Hide platform & the Wet Feature which is currently closed off with extensive engineering work taking place. 

 

The Danger Area (DA) is fully re-opened and the only obvious visual differences are that the doors of the buildings are now blocked with notices attached.

 

The keys for Buildings P5 and P6 also available & we will keep you updated.

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Tunnels​​

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Rhydymwyn Buffer Depot and Tunnels Access in 2026 - Part 4

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From the end of last year (2025) when the site closed for refurbishment many changes were made to the site and completed, before the re-opening at the beginning of May.

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The major parts effected were:

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1. Access (1). The Danger Area (DA) has been fully re-opened, the only obvious, visual differences are that the doors of the buildings are now blocked with notices attached.

2. Access (2). The Wet Feature is currently closed off for extensive engineering work to take place.

3. Access (3). The Woodland Path now terminates at the boundary to the DA, and it has been made safer with extra signage.

4. Library (VC). We believed that a secure library for important and key documents would be provided in the VC, but it appears this is not the case.

5. Tube Alloys (TA). Building 45/P6 is the most famous building on the site and is of international importance. It is where the original Simons Separation Engines were tested to prove the efficiency of the gaseous diffusion process which led to fissile material being produced on an industrial scale. During the close-down Defra made repairs and clearances to the Grade II listed building and we now have all year access through it. We understand the roof is about to be repaired and we need to have documentary evidence of all the changes to the building to complete our records. We may have an agreement that we will set it up as a Tube Alloys Building. We must express thanks to Defra for these major works, which were unexpected.

6. The Tunnels. We are informed that major engineering activity is being carried out and this may continue into 2027. So, works are still in progress, and as an accommodation, Defra offered us limited access to the North Tunnel inside a Heras fencing cage. Whilst we are grateful that they have gone to such efforts on our behalf, we do not think we can do this without giving undue risks to our tourists. Since Ken Skates originally opened the tunnels for us, we have had a rocky road with gaining access, with several cancellations for various reasons. It is the general preference that we wait until the works are completed and then re-open them with a secure and reliable agenda, which will also allow us to re-organise RVHS as a reliable and stable unit.

7. The Future. We will now start to arrange a meeting where one of the top items will be if you (the membership) wish to take advantage of the accommodation offered by Defra.

 

One final consideration is that the new site induction protocol has been changed in many ways. We believe we may be reduced to taking tour parties on the site, but it must be read in conjunction with what wish to do on site.

Best Regards

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Colin

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NB - Added a new video from Youtube of "Steam on the Wirral", showing storage of Uranium Ore at Thurstaston station goods yard (and Parkgate), and was intended for use at the Capenhurst Uranium separation plant.

 

Although not directly connected to Rhydymwyn, it illustrates the scale of the UK Post-WW2 nuclear operations. It is on the "Links" page, and repeated here (skip to 20:08) : (Uranium Ore on Youtube).

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