Margam Auxiliary Unit Patrol
Thank you for selecting information on
the Margam Auxiliary Unit and Operational Base near Port Talbot. The info and images below have been kindly
supplied by Aux researcher Jason Grey.
This page was last updated at 11:42am on
Research into this patrol and its training is ongoing. The information below is published from
various sources and is by no means conclusive. If information is not listed below
it does not necessarily mean the information is not out there but normally means CART researchers
have not found it yet.
If you have any information on this patrol or can help with research in this area please do
The Area: No 19 GLAMORGAN (Part – Groups 4a & 4b) , MONMOUTH Group 3, HEREFORD Group 2, and WORCESTER
Groups 1a & 1b.
The patrol was part of GLAMORGAN GROUP 4B: which consisted of five Patrols: “Pen-y-Fai”, “Coity”, “Heol-Y-Cyw”,
““Ewenny”, and ““Kenfig Hill” patrols.
Group commander of these Patrols was Lt. Leyshon Owen + Assist. Group Commander 2nd Lt. William Stafford
Aubrey Eric Groom (Patrol Leader)
Albert Francis Groom
Frederick Thomas Groom (Called up & served in Africa/Middle East 1940)
Dillwyn Rhys Thomas
Gwyn Marsh Harding
William David Mills
4 members of the patrol indentified due to family connection, other members identified from an official
list. The three identified members were brothers in reserved occupation, Mining, and Forestry commission, and all
had unique knowledge of the local geography due to the family being the Estate Manager/Gamekeepers on the Margam
estate for 30 years prior to WW2.
The OB is located on steeply sloping escarpment. The location was tactically excellent as it would have been
impossible for troops to approach without being seen or heard approaching, and with potential escape into a huge
The main structure is intact, with no signs of previous discovery. Main entrance cover/tray has collapsed, but
mechanism/structure remnants may be contained under the soil and leaf detritus at the bottom of the access shaft.
Roof is intact, although rust is quite evident at the sides. Brick structure all sound.
Escape shaft tunnel has collapsed with a large mound of earth and leaf foliage forming a partial obstacle to the
escape exit, but is still passable (April 2013). The escape tunnel was actually constructed as a trench, using dry
stone walling on both sides of the trench, and then a tin roof cover placed over the top and topped with earth to a
depth of 2-3 feet. It looks like the roof was flat rather than arched, and as such collapsed under the weight
of earth and corrosion due to poor drainage. The stones used were probably collected from roman fort/camps that
scatter this area!
Escape trench runs for about 8 meters (estimate from memory, so needs checking) before leading to a left hand
90 degree branch of about 2 meters further length, and continues for another 2 meters before bifurcating into
2 endings. There looks like some kind of vertical channel or groove constructed into one of the ends, and there is
a wood prop within the groove. Potentially this makes 3 points of escape exit, with one of them maybe having
some kind of mechanism to activate?
Size of OB and entrance/exit etc: To be confirmed by further survey
Orientation of OB: To be confirmed by further survey, but crudely estimated to run South to
North, with the southerly point being the main entrance.
Observation Post: Not known, and no evidence of one.
Other physical remains nearby: None found, although a local quarry was used for combat &
small arms training.
Kenfig Carbide Works, Aberbaiden Colliery, Railway sidings, and marshalling yards south of what is now Eglwys
Nunnedd Reservoir, and main tracks running east west to Port Talbot steelworks, and port Talbot Docks, Margam
Castle could have been a potential billet/HQ for German troops stationed within the area, and their water supply
could have easily been accessed! Main road from Bridgend to Port Talbot (now the A48), plus railway bridges
at Stormy Down, Kenfig etc. Stormy down Airfield,( although the Pen-y-Fai/Tondu patrol would probably have
covered this more easily)!
Unknown, but it is assumed that they had the standard weapons and explosives issued to all patrols.
Dillwyn Thomas has also written a book which can be purchased in our shop.
In November 2013 Margam Auxilier Dillwyn Thomas marched at the Cenotaph for the first time.
You can see him marching here
Dillwyn Thomas talking on Newyddion 9 on S4c - 11th November
Dillwyn Thomas talking to ITV Wales - 11th November
OS Maps 1897 and 1947, TNA WO199/3389, & data from Stephen Lewins
If you can help
with any info please contactus.