Secret Bases & Hidden Places

Criggion Communications Base

Why was a quiet area of rural Wales once a Nuclear Hotspot ?

Just a few miles outside of Welshpool in Powys, under the shadow of the Breiden Hill and 'Rodney's Pillar', the area shown in the photograph was once one of the Russian's prime nuclear misile targets.

It also played an important role in WW2 and the Falklands war.

This is what was there !

Criggion is a area of mostly flat farm land tucked just off the A458 Shrewsbury to Welshpool road, laying between Bausley and Trewern. Hidden on one side by a quarry and the 'Breidden Hill', the home of Rodney's Pillar, a monument to Sir Admiral Rodney which stands at over 900 Feet, and visible from many miles around.



Criggion radio station was born as a direct result of Hitler's war and the Admiralty's realisation that Rugby's VLF transmitter (callsign GBR), vital to the war at sea, had no standby and might be severely damaged or destroyed by stray bombs intended for nearby Coventry.

A crash programme was therefore set in motion in 1940 to remedy this situation and to provide additional high frequency (HF = medium wave) radio transmission capabilities across the Atlantic. The aerial for a VLF transmitter occupies a large area (because of the long wavelength) and needs very high masts to support it, and since only three suitable 600 ft. high masts were available in the country at that time, it was decided to seek a site where they could be located on a large plain flanked by a hill to provide a fourth anchorage. 

In September 1942, the first HF transmitter was put into operation, and early in 1943 while Criggion's VLF transmitter was still in the testing stage, Rugby's GBR station caught fire (not due to enemy action). Testing at Criggion was accelerated and within just three days Criggion's new transmitter had taken over the Admiralty service to HM ships at sea. It was a lucky break, for Rugby was out of action for over six months. Criggion's GBZ played an important part in the sinking of the Scharnhorst and the capture of the Altmark, and letters of thanks were received from the Admiralty for the assistance given. 

Map showing the building and mast locations

The masts were so high supporting cables were attached to the winch house on top of Breidden Hill for support, these cables constantly needed re-tensioning due to expansion or shrinkage of the metal through changes in temperature.

So important were the masts that they had high armed sentry posts for protection. Even after the base had been 'stood down' and right up to the time the masts were removed security was still very high, if you drove along the narrow dusty lane you were observed by cameras, and if you stopped your vehicle then a plain unmarked security vehicle would appear almost instantly.

The winch house on the hill was permanently manned and included bunks and a kitchen. The access to the top of Breidden Hill and the winch house was very dependent on good weather, the access is at an angle of 33 degrees and in winter months when snow was down some staff had to stay at the winch house for days on end and sleep on bunks. The area surrounding the base is also very prone to flooding and even now sometimes completely cut off from the main roads. The Station Commander once had to swim out to reach the base from the main road, and a amphibious DUKW vehicle was from then permanently stationed for his use at Criggion.

So what was in these buildings, and what did they do?

The Very High (VHF) and Very Low Frequency (VLF) Transmitters main function was to communicate with the Trident Submarine Fleet around the world whilst far out at sea.

The plain white square transmitter buildings were just the icing on the cake. Buried deep below ground is a large complex housing all the communications equipment.  It was this equipment that transmitted the order to sink the Scharnhorst in 1943, it also gave the order to attack the Belgrano on the 2nd May 1982 and to invade the Falklands.

Criggion Base in the 1940's

The spread of the multi-level complex below ground is not fully known, these photographs are from just one building, but there were two others. But even when driving along the nearby road my CB radio would go haywire, and the signal meter would hit full strength even when the CB unit was turned off!

Radio Transmission Aerials have to be adjusted or 'Matched', altering the physical length of the the aerial to match the electrical length. Those that have used CB radio's will remember using a SWR Meter to measure the Standing Wave Ratio of their antennae, and maybe using a 'Matcher' to adjust it. These aerials needed the same, just something far bigger!

Demolition of the Masts

The massive transmitter masts were blown up and demolished in 2003 but the buildings remain.
Further information can be found at

Knockin Satellite Dish

When the Transmitter Masts were removed from Criggion a massive Satellite Dish suddenly appeared just a few miles up the road in a quiet country lane on the edge of some farmland in Knockin.  It appears very out of place in a farming community and it seems a very odd place to locate it, almost completely obscured from view from the road by trees, yet so close to a school and village community, in a lane rarely used by passing traffic, even some locals are unaware of its existence. I only found it by accident when driving through the lanes, a child on board my vehicle felt sick and I pulled over at the side of the road and I caught a glimpse of it through the trees.

Why was located here? Obviously the land it sits on has to be rented or purchased at a high cost.

Why was it not built on the existing communications site at Criggion and use made of the existing
buildings, cabling, power supplies, and of course the staff already in existence ?

This is no standard telephone mast as we now often see scattered around to provide a mobile phone service, compare the size on the pictures above against the size of roads and nearby buildings. it is that big that at first view I thought it was a old wartime Radar Dish and expected to find a RAF station behind it.  Instead just like the base at Criggion, a sign tries to lead you to believe its nothing and owned by Brittish Telecom.


To me the dish more resembles the dishes at Madley Earth Station or those at Goonhilly Downs, its constantly moving about so it is possibly a tracking Satellite, but a tracking Satellite for what ?

(for further information regarding these Earth Stations see below)


So, is it really as they suggest ? 

'Just' for telephone calls ?????

Madeley Earth Station

'Madley Earth Station'
Opened in 1978 in Hereford has similar dishes.
It has over 50 satellite antennae, 47 which suppsedly provide voice, fax, data, IP and TV.

Yet it is believed to be one of the largest Secret Defence Satellites tracking stations.

Madeley Earth Station

The 'Official' story by BT

Goonhilly Downs

Goonhilly Downs

which is 25 miles from Lands End opened in 1962 to track the 'Telstar' Satellite.

It is also the land based terminus for several high capacity sub-sea communication and data cables.

Goonhilly Downs Tour (2005)

Goonhilly (2016)

Goonhilly (2017)

The Knockin dish may be just as they say a communication transmitter for mobile phones etc., but it's location seems odd, it is distant from any known telephone exchanges, it is also located in an rural area which does not use 'cabled satellite tv'.

Unlike Goonhilly it is also far from the sea so it is obviously not a terminus for sub-sea communication cabling.

What do you think ?

One good thing about its closure as a 'Communications Base' is that hopefully we are no longer on Russia' hit list for first strike!