GW/BR(W) coach identification.

[Re6/6]

Can anybody identify what coaches these might have been please?

 

They are on a 'colliers workman's' train at Glyncorrwg. Could they have been a couple of ex-auto coaches?

 

Cty Hodge and Davies 'Tondu Valleys' by Pen and Sword.

[exet1095]

They’re both Mainline and City break thirds, both preserved (and one restored) at Didcot.

https://didcotrailwaycentre.org.uk/article.php/148/no-3755-churchward-non-corridor-brake-third

https://didcotrailwaycentre.org.uk/article.php/149/no-3756-churchward-non-corridor-brake-third
Paul 

[The Johnster]

I can understand your impression that they might have been auto trailers.  The Glyncorrwg workmen's trains served collieries that were at the far northern end of a particularly remote, steep sided, and narrow bottomed valley even by South Wales's standards, and the branch itself was pretty steep and very sharply curved.  There was little room up there for runaround loops, and the trains worked normally from their southern terminus at Cwmmer Corrwg as far as the village of Glyncorrwg, the last point of what passes for civilisation in that part of the world (it's got a pub, it's the last  place where people actually live), where the loco runs around and propels the train the rest of the way up the valley.  Mineral workings were handled in the same way.

 

This was authorised in the local Sectional Appendix, and the guard was required to 'keep a good look out' during the propelling movement, and to assist him in this task, windows were cut in the guard's comparment end, similar to slip coach pattern, and he was given a foot-pedal operated bell to frighten the sheeps with, same as on auto trailers.  There was no auto linkage and the locomotive, almost always a 57xx or 8750 (Dyffryn Yard job), was not equipped with auto gear.  The guard had a brake 'setter' in the compartment, as all guards' compartments did, and could if needed use it to apply the vacuum brake and stop the train in an emergency.  It was a sort of ersatz auto train.

 

The Main Line & City stock (there were full 3rd as well) was the last used on these services, which were the last revenue use of them, ending in 1962 after which the collieries all had pithead baths and the men could use buses though the mineral workings continued.  Prior to 1958, the last revenue clerestories were used, and had similar end window and bell arrangements. the end windows being larger and looking more like an auto trailer, but these were converted from all thirds and had no brake compartment.  I am not sure if the guard could apply the vacuum other than by means of the communication cord.  Until 1954, the last Dean 4-wheelers were used, and these had a single lookout window in the guard's compartment end, centrally, a setter (of course), but no bell.  One wonders if a near miss or a few sheep incidents led to it's provision on the later stock.

 

The Main Line & City coaches were repainted in 1956 in BR unlined maroon, and served out their days in this livery being kept creditably clean, which is more than can be said for their predecessors.  It is difficult to determine what livery the clerestories were in, though it does not look in photos like chocolate and cream.  It could be 1942-5 austerity GW brown, or dirty BR crimson, or, at a push, prewar workmen's stock plain chocolate, but in BR days they coaches carried BR Gill Sans numbers. 

 

The 4 wheelers, from photographs, were so dirty as to render the livery irrelevant; there were some of these coaches given BR crimson livery at Caerphilly Works in 1949, but I'd feel fairly safe in stating that none of those worked here and were more likely used on the Senghenydd workman's.  They had come a long way from their fully lined out late Victorian splendour, but the panelling gave them a residual dignity even at the end; this was true of all of the Glyncorrwg coaches.

Edited January 17, 2022 by The Johnster

[Siberian Snooper]

Thanks for the info, it's very informative. The colliery workings in South Wales are something of a mystery to most of us and any enlightenment is welcomed, at least to me.

 

 

[bécasse]

There were a number of miners' 4-wheelers which had what had previously been a normal passenger compartment labelled as a guard's compartment (in this case without an end window). I have always assumed that (at least) one bench seat was removed and a brake setter installed - it would have been a cheap enough conversion.

 

Most of the miners' 4-wheelers were in overall brown livery, and I suspect had been well before WWII, and presumably the earlier Glyncorrwg bogie vehicles were the same. As has been said, final repaints in BR days were into Crimson, seemingly always unlined.

[br2975]

The ex-GWR four-wheeled stock used between Cymmer Corrwg - Glyncorrwg - South Pit Halt and North Rhondda Colliery Halt included;

W2766W, W2775W - Dia. S9 of Lot 760, built 1895

W238W, W2799W -  Dia. S17  

W2691W, W2692W - Dia. T34 of Lot 761, built 1895

These were scrapped between 1951 and 1953 when the clerestory stock took over.

.

The 'Mainline & City' stock remained in use between Glyncorrwg and South Pit until 1964.

.

 

 

Edited January 17, 2022 by br2975

[br2975]

Workmen's services ran in this, the remotest valley in the  South Wales coalfield until the closure of Duffryn Rhondda Colliery, located south of Cymmer (Afan) in the Afan Valley, until November 1966. 

.

Cymmer (Afan) was on the Bridgend - Treherbert line, whilst Duffryn Rhondda Colliery was a mile or two south of Cymmer, on the former R&SB line, by now freight only, and only open twixt Cymmer and Duffryn Rhondda.

.

A pair of  Cl.121 single car DMUs worked the Bridgend - Treherbert service, and at shift change times, the DMU would arrive at Cymmer from Bridgend (or Llangynwyd) then, for the benefit of the miners,  reverse down the freight line to Duffryn Rhondda, before retracing its steps to Cymmer, then reversing to return to Bridgend (or Llangynwyd)

.

One service left Duffryn Rhondda for Cymmer, thence Treherbert, requiring the miners to change trains at Cymmer.

.

This unadvertised, but official workmens diversion ceased  when mining ceased at Duffryn Rhondda in November, 1967.

.

But, the washery remained open, fed by coal from Avon Colliery, Abergwynfi, and Glyncorrwg Colliery................requiring the attention of (i) two Cl.14 locos which worked up from Margam each day, (ii) a Cl.37 to remove the coal from Cymmer, and a (iii) Cl.47 which worked a daily MGR train to and from Aberthaw Power Station, and which was split at Cymmer for tripping to Duffryn Rhondda

.

.

.

 

Edited January 17, 2022 by br2975

[The Johnster]

South Wales is pretty confusing to most of us who live here, never mind the problems poor outsiders face trying to get a handle on the place.   To clarify, Duffryn Rhondda and North Rhondda were pits in the Afan and Corrwg Valleys respectively, and nothing to do with the Rhondda Valleys further east across the mountain.  These 2 collieries were named for the Rhondda Main coal seam that they were sunk to exploit, and not the Valley.

[br2975]

Pit owners whose mines were outside the Rhondda valleys often included names such as "Rhondda" and "Merthyr"  in order to associate themselves with better quality coal, or to secure markets by implying that their product was as good as that hewed in the Rhondda or Taff valleys.

 

[The Johnster]

Well, sort of.  The Corrwg and Duffryn Rhondda pits are named after the seams, which were fairly consistent in quality over a fairly wide area which might include several valleys before that particular seam tapered out.  Coal was ordered by the customers, particularly the industrial and overseas customer, through agents who arranged the shipping.  As the boilers of various concerns, and the processing in gas works and similar industries, were designed to deliver their maximum efficiency with coal of specific provenance, this was important, as different coals, sometimes from different seams in the same pit, had different calorific value and sulphur content, as well as (sometimes) differing friability, which affected the handling equipment.  Different coals needed different storage as well, as some were more liable than others to spontaneous combustion from chemical reactions.

 

So the agents would order mixes of coal to be delivered to docks for export or block transport to steelworks or other large industrial facilities.  As not all the collieries could supply all the components of all the required mixes, there were storage sidings closer to the ports where apparently pointless shunts of what looked like, but weren't, identical loaded wagons of coal took place (I used to watch these as a child at Crwys Sidings, on the Rhymney in the northern suburbs of Cardiff. and be totally mystified at what was going on until a friendly driver on a 94xx gave me a cab ride and explained the situation to me) to make up trips to the docks that would provide the requisite mixture when they were tipped into the ships' holds. 

 

The export trade was very largely concerned with basic sorts of coal for different purposes.  Porbably the biggest in terms of tonnage was bunkering coal, necessary in the days of steamships and taken to the bunkering ports of the empire, Gibraltar, Alexandria, Aden, Colombo, Hong Kong, and Singapore, to refuel steamships.  The Royal Navy had their own colliery in Tonypandy for their ships, manned by naval ratings, but the coal was taken to the bunkering ports in merchant ships.  Then there was coking coal for steelworks use, exported to coking ovens in France, Belgium, Holland, and Northern Spain.  Another major component of the export business was gasworks coal to produce Town Gas, and this went everywhere there were towns and cities with gas lighting or gas mains systems.  The Opera House of Manaus, 1,500 miles up the Amazon, was lit by Welsh coal, as were the villas of businessmen in Valparaiso and Sydney.

 

It was a complex and intricate business of which the railway part was only one component, and it worked with remarkable efficiency considering the sheer level of traffic.  Ports competed with each other for a slice of the pie, but inevitably Davies collieries used Barry, Cory, hand in glove with the Butes, used Cardiff, and so on.  Each port had different capacites; for example Cardiff had the longest sea locks, Newport the deepest, and Barry the widest, important factors when you took into account the size of the largest ship able to use the port, or the combination of smaller ones that could lock in or out at the same time.  Barry was constructed largely in response to inadequate wharfage at Cardiff, which caused major delays and made owing pubs on Flat Holm and Steep Holm a profitable undertaking as crews rowed over from anchored ships awaiting berths.  One sees old photos of the West, and even the wider East, Docks at Cardiff jammed side to side with ships.  The cause of this was inadequate hydraulic power to operate all the coal hoists simultaneously at a decent pace as well as the lock gates and swing bridges, and the new docks at Barry featured more and more powerful hydraulic pumping stations, all steam powered from coal fired boilers of course.  Cardiff answered with the big new Queen Alexandra Dock, which featured mobile hoists that could move along the wharf so that a more efficient use of it could be made, but this was at the cost of having to hoist the wagons from ground level and move the hoists to the end points of the feed sidings.  Swansea had mobile hoists as well, the last of the Bristol Channel ports to export coal, well into the 70s.  Cardiff tipped its last wagon in 1965.

 

The trend from 1840 onwards was for steel hulled ships and the size began to rise, and Porthcawl was an early victim of this, as it became unviable in the Edwardian period, managing to shut at a time when traffic was still increasing exponentially; after the Great War it went into terminal decline over the next 50 years, not helped by the National Strike in 1926 or the Great Depression following the 1929 Wall Street Crash.  Penarth was next, closing in the 30s, but kept itself going for some time with a reputation for the fastest and most skilled trimmers.  Trimmers moved the cargo around in the hold to stow it firmly and safely after it had been tipped in, a filthy, dangerous, and high paid job, very necessary as the seaworthiness of a ship not properly trimmed could be and sometimes was impaired; ships and crews were lost because the coal moved around in the holds.  Fast trimmers saved the shipowner wharfage and loading fees, especially in the Bristol Channel ports where the tidal range meant several hours delay if a ship missed a tide, and big savings if it caught one ahead of schedule.  Ships only make money when they're at sea.  Furthermore, if a lock could be shared with other vessels, the cost was split between them on a tonnage basis, and missing such an opportunity might make the difference between profit or loss on a voyage.  Penarth had been used by the famous 'Flying P' line windjammers, 5 mast barquentines able to outrun and undercut the running costs of steamers despite having larger crews even in the 30s.

 

Coal isn't just black rocks, there's much more to it than that!

[KingEdwardII]

Great summary @The Johnster.

 

A couple of books that can throw more light on the South Wales valleys and the coal trade are:

 

"Rails in the Valleys" by James Page

- a great overview of the railways right across South Wales, including how they were operated, covering the coal trade in particular

 

"Cynon Coal - History of a Mining Valley" by Cynon Valley History Society

- concentrates on the history of coal mining in just one valley, although one with a long tradition which also included the iron industry.

- lists an astounding 309 separate collieries, which include levels and drifts, going back to the very start of mining in the valley in the 18th century. The very last deep mine in South Wales - Tower Colliery - was in the Cynon Valley.

- all this in a valley that is said to have been so rural in the 17th century that a squirrel could go from Abercynon to Hirwaun without ever touching the ground, there being so many trees

 

Yours, Mike.

[The Johnster]

I have 'Rails in the Valleys' by James Page, basic essential for anyone with an interest in the area,  My connetion with it was a Great-Aunt Nell who lived in Tonypandy, 104 in 1965 when she died.  Her parents were Irish refugees from the Great Famine, and she lived all her life in the house she was born in; she also reckoned that she could recall a time when a squirrel 'could go from Porth to Blaencwm without touching the ground', but the trees were soon all felled for pitprops.  She was something of a character, tough as old boots with a grip that terrified me, but I loved going up there on visits.  In summer you could play on the mountain. 

 

But my real interest in Valleys railways came about in 1958, when I was 6, when father took me up the Garth, not a horrible euphemism but a mountain near Taff's Well.  From the rocky outcrop at the summit one could overlook that part of the Taff Valley and the Tongwynlais gap, and it was spectacular; I'd never seen anything like it, and, as the traffic lessened, never would again!  Trains were running everywhere you looked, several of them on the TVR but also visible ascending and descending Penrhos bank, one traversing the Walnut Tree viaduct, one waiting for the road off the new connection to Nantgarw colliery, and one in the distance on the PC&N.  With the road traffic, it was all action and wonderful entertainment, and I never experienced anything like it again in the UK, but some 8 years later on a family camping/touring holly spent a very happy evening in not dissimilar vein overlooking the Rhine at a place called Martinsburg, a constant stream of barges going up and down the river and trains on both banks, again with road traffic as well.

 

Further up the valleys was all action as well, as there were always collieries, with locomotives shuntiny, pithead wheels running, and the ariel buckets.  I never tired of these, they absolutely fascinated me, spoil being taken by cableway in bucket cable cars up the mountain to be tipped and the empties coming back down at a steady pace.  When coal was being wound, they were in continual operation, and the squeaking and clanking was so persistent that you became unaware of it after a while, then it stopped and everbody looked around wondering what had happened for a second.  The sheer intensity and scale of it all is difficult to imagine for generations who never saw it, and a same age friend who was brought up in Tonyrefail was recently telling me how she was trying to show a visitor where the colliery and the coke ovens had been at Coed Ely, but the landscape had changed so much that it was difficult to picture the former scene.

 

Tips, fed by the ariel buckets, dominated the landscape in every direction, fresh black spoil making them stand out against any background.  Those that remain unlandscaped are greened over now, and not as obvious; you can see them but you have to look, and tune your eyes in to the subtleties of the landscape.  And the trees are back, sadly mostly in the form of regimented rows of Forestry Commission plantations which look (because they are) every bit as disfiguring as the tips and industrial mess that preceded them.

 

As a modelling subject, the area has a lot going for it, especially my chosen area, the Tondu Valleys, single track branches worked to absolute capacity so that running (as I do) to a real time timetable is challenging enough to keep me satisfied with the layout I've got despite the size limitations.  There isn't much dead time!

[br2975]

There are now far more numerous published resources relating to South Wales than for many years past.

.

However, the South Wales and its' valleys remains something of a railway backwater to many enthusiasts

.

eg look at all the published photographs of Western Region hydraulics, and you'd be forgiven for thinking they rarely, if ever ventured through the Severn Tunnel into Wales.

.

As a taster, there are several 'series' of books which will give a greater understanding of the South Wales railways; all are highly recommended.

.

"Steam in South Wales" a series started by Michael Hale and completed by the Welsh Railways Research Circle........excellent books, but be prepared to pay.

.

"Rickards Record "  a series of three books started by the late Brian Miller, featuring the photographs of the late Sid Rickard. Many of the photos featured earlier in the two Bradford barton tomes "Steam in South Wales" and "More Steam in South Wales". However, the later, 'Rickards record' series contain much more local information.

.

The series of books by John Hodge, started by tracing the South wales mian line westward from the Severn Tunnel, and then the North & West route north from Newport; before starting on the valleys. The author was a railwayman, and the operational information in his captions generally 'spot on' and very useful.

.

Tony Cooke's trackplan books of the GWR & BR (WR) are indispensible.

.

"Collieries of Wales" is also a very detailed tome, outlining the developments of mining, and cvoal mines in the South Wales coalfield.

.

Of course, there are other related books, but these come off my bookshelf the most.

[The Stationmaster]

Also covering more or less that area of the coalfield  (all are paperback volumes unless shown otherwise and are basically informatovely captioned assemblies of photos) -

 

South Wales Collieries by David Owen published by Tempus (he also wrote books on both of the Rhondda Valleys)

Rhondda Collieries by  David Carpenter

Taff Vale Railway - 3 volumes,  from Silver Link Publishing

Rhymney Railway - 2 volumes , same publisher

Cardiff Docks, - 2 volumes, same publisher 

Rails To Prosperity - by Brian Miller, about the Barry Rlwy

The Aber Branch - hardback - by Colin Chapman published by the WRRC

 

And of course Tony Cooke's magnificent volume covering the whole South wales coalfield published by Lightmoor Press.

[Tom Burnham]

Couple of photos by Derek Chaplin recently posted on Flickr which show miners' trains in S Wales -

 

 

 

[br2975]

A few more books with a South Walian bias...

.

"The Ely Valley Railway, Llantrisant - Penygraig" by Colin Chapman, pub Oakwood Press

"The Llantrisant Branches of the Taff Vale Railway" by Colin Chapman, pub Oakwood Press

"Taff Vale Lines to Penarth" by Eric Mountford & Neil Sprinks, pub Oakwood Press.

"The Vale of Glamorgan Railway" by Colin Chapman, pub Oakwood Press

also, a lovely colour album is

"Steam in South Wales" by Derek Huntriss, featuring the  photos of Alan Jarvis, pub Ian Allan

.

There are more

[br2975]

From a local history group on the 'Book of Face'

.

An extremely busy time at Cymmer Afan South Junction, circa 1964.

.

Out of view bottom right is Cymmer/Caerau tunnel through which the single line to Maesteg, Tondu and Bridgend left this, the Afan Valley to reach Caerau in the Llynfi Valley.

.

The Afan Valley goes from left to right, and on the extreme left can be seen a signal on the former R&SB line, which by this time only went as far as Duffryn Rhondda Colliery, about a mile south west.

.

The solitary pannier is on the branch to Glyncorrwg, which crosses the Afan Valley on a viaduct, before reaching the 'platform' at Cymmer Corrwg, the platform hut of which can be made out, across the valley, and  directly above the Class 37.

.

The miners trains initially started at Cymmer Corrwg, and travelled up the next valley to Glyncorrwg, thence onward to South Pit Halt etc.

.

Such passenger workings were not allowed across the viaduct, in fact when the Swansea Railway Circle ran a pannier hauled excursion to Avon Colliery and Glyncorrwg circa 1964, the passengers were required to detrain, and walk across the road bridge from Cymmer (Afan) station to Cymmer Corrwg, where they rejoined their train......but, several ne'er do wells had hidden in the 'bogs' and travelled across the viaduct, contrary to orders !

.

The Cl.37 is on the 'mainline' that curves around toward Cymmer (Afan) station, whose 'plywood wonder' signal box, commissioned in 1960 following track and route rationalisation here, can be clearly seen.

.

The stone building partly hidden by the 'plywood wonder' was the station refreshment room, on the former R&SB station, and which still survives as 'The Refresh' and well worth a visit.

.

The R&SB railway falls from behind the signal box, to pass under the viaduct, hence the signal mentioned at the start of my post.

.

With the closure of the Rhondda Tunnel, the Bridgend - Treherbert passenger service was cut back to Cymmer Afan, and really only survived due to the local schools contract, which finished with the end of the summer term in July, 1970.....frieght traffic having already ended with the closure of firstly Glyncorrwg Colliery, then Avon Colliery which was further  up the Afan valley at Abergwynfi, all of which in turn spelled the end  for Duffryn Rhondda washery.

 

Edited January 19, 2022 by br2975

[br2975]

Exactly 52 years ago

Wednesday, 21st. January, 1970

.

Duffryn Rhondda washery closes and the 15:45 Aberthaw – Duffryn Rhondda and return MGR service ceased.

The MGR service now loading at Llynfi Junc.  

.

Duffryn Rhondda – Cymmer Afan remained open to serve the loading of coal from a private mine.

Arrangements planned for loading to be carried out at Cymmer and the branch closed.

.

Duffryn Rhondda was to be served twice weekly by the Cl.08 Glyncorrwg pilot .

 

Glyncorrwg Colliery is due to close on 1st. May, 1970.

.

The only freight now working to Cymmer was the 22:45 ex Margam, returning at 02:00 

[The Johnster]

On 19/01/2022 at 09:11, br2975 said:

There are now far more numerous published resources relating to South Wales than for many years past.

.

However, the South Wales and its' valleys remains something of a railway backwater to many enthusiasts

.

eg look at all the published photographs of Western Region hydraulics, and you'd be forgiven for thinking they rarely, if ever ventured through the Severn Tunnel into Wales.

.

As a taster, there are several 'series' of books which will give a greater understanding of the South Wales railways; all are highly recommended.

.

"Steam in South Wales" a series started by Michael Hale and completed by the Welsh Railways Research Circle........excellent books, but be prepared to pay.

.

"Rickards Record "  a series of three books started by the late Brian Miller, featuring the photographs of the late Sid Rickard. Many of the photos featured earlier in the two Bradford barton tomes "Steam in South Wales" and "More Steam in South Wales". However, the later, 'Rickards record' series contain much more local information.

.

The series of books by John Hodge, started by tracing the South wales mian line westward from the Severn Tunnel, and then the North & West route north from Newport; before starting on the valleys. The author was a railwayman, and the operational information in his captions generally 'spot on' and very useful.

.

Tony Cooke's trackplan books of the GWR & BR (WR) are indispensible.

.

"Collieries of Wales" is also a very detailed tome, outlining the developments of mining, and cvoal mines in the South Wales coalfield.

.

Of course, there are other related books, but these come off my bookshelf the most.

 

The top photo, cover of Michael Hale's 'Steam in South Wales' shows North Rhondda Colliery in the mountain fastnesses of the upper Corrwg Valley, and well illutrates the lack of space at this location, and the steepness of the branch.  Everything is hemmed in between the precipitous mountainside and the Nant Corrwg stream, and on the opposite bank the mountain rears up straight out of the stream bed.  In fact the railway is built into the stream bed and there are brick, stone, and concrete retaining walls.  The Corrwg was not the only valley like this, but probably the most extremely so.  There is nothing else there but the colliery, not even farms, and the village of Glyncorrwg is 2 miles away.  Even the sheep think it's a bit isolated...

[Re6/6]

On 19/01/2022 at 09:11, br2975 said:

 

"Steam in South Wales" a series started by Michael Hale and completed by the Welsh Railways Research Circle........excellent books, but be prepared to pay.

.

I've manage to locate a copy of Vol 1 at a sensible price. Thanks for the recommendation.

[br2975]

 

"North and South Rhondda Collieries Glyncorrwg circa 1954"  by Derek Chaplin - Peter Brabham collection on Flickr.

[br2975]

The Cymmer Corrwg - Glyncorrwg and North/South Pit miners train, at Cymmer Corrwg, 1955 - with the clerestory rake then in use.

.

 

[The Stationmaster]

12 hours ago, br2975 said:

 

"North and South Rhondda Collieries Glyncorrwg circa 1954"  by Derek Chaplin - Peter Brabham collection on Flickr.

Thanks for the tip about that collection - some top notch stuff in there.

[KingEdwardII]

19 hours ago, The Johnster said:

The Corrwg was not the only valley like this

Makes the Cynon valley at Aberdare look like a vast open prairie! There is space there for schools and playing fields on the flat land at the bottom of the valley and there was quite a trek on the flat from the hillside at Blaengwawr crossing the Taff Vale line, the Cynon and then the GWR Neath-Pontypool line before getting to the opposite hillside at Cwmbach. The Cynon valley is also unusual in actually opening up as you head up the valley until reaching Hirwaun Common.

 

Before the railways, it was flat enough for a tramroad to make its way across Hirwaun common from the Ironworks at Llwydcoed westwards towards the head of the Neath valley where there was an inclined plane dropping down to the canal there. Later all replaced by the Neath-Pontypool line.

 

Yours, Mike

[The Johnster]

Geomorphology.  The story here is that the central Glamorgan plateau was subject to the spread of the ice sheets of the last Ice Age, which ultimately extended southwards to a line more or less coeval with the current route of the M4 across the county between Cefn Mably and Port Talbot, built on it's terminal moraine because this was less valuable as agricultural land and cheaper to compo the farmers for.  The ice formed into glaciers along the routes of previous valleys, cutting them into the relatively straight, flat-bottomed valley forms you now see at Aberdare, or between Ton Pentre and Treherbert, or Caerau and Maesteg, or Quaker's Yard and Merthyr, in fact right up to Storey Arms. 

 

Further south, the ice did not have the momentum or weight to cut these glacial valleys and the river-eroded v shape and interlocking mountain spurs are more common, such as at Tonypandy, or between Quakers Yard and Abercynon, where a fault complicates matters.  In many places, of course, there is a combination of these features.  At Glyncorrwg and the northern reach of that valley, a stream that has developed consequent to the retreat of the ice some 12,000 years ago has cut a very deep and narrow v shaped valley form as it drops from the heights to the north to the Afan at Cwmmer, some 1,200 feet in about 5 miles providing the erosive force for this.  It is very noticeable in comparison with the sweeping plains of Aberdare, or even Treorchy, but similar very steep and narrow valleys are eroded in to the plateau massif above Treherbert, the 'cut' used by the Rhigos road out of the Rhondda being one.

 

At the heads of valleys like the Ogwr, Garw, Rhondda Fawr and the Afan, there are the characteristic 'cirque' or 'corrie' semi-circular rock outcrops at the edge of the plateau and the corresponding precipitous scree drops, which are where the deep snow-fed icefields that fed the ancient glaciers were formed.  The ice sort of sucks at the mountainside as it begins to move down the valley and these formations result. 

 

The Afon Cynon is a more complex affair, and you may remember learing in your geography classes at school, if you were awake at the back, about 'river capture'.  The ancient Cynon was at one time fed by streams rising just to the south of the great escarpment of the Fforest Fawr, the Dringarth, Llia, Mellte, Hepste, and Nedd Fechan.  These flowed south and then southeastwards through Penderyn to feed the Cynon, but there is a geological fault running up the Vale of Neath, another classic glacial valley, and when the glacier melted, new streams from the head of it at Pontneddfechan cut into the uplands and 'captured' the ancient Cynon's headwaters, the drop being very steep and allowin these streams to cut powerfully downwards to produce what we now think of a 'Waterfall Country', a perfect geological storm of limestone edges over which the streams drop spectacularly. 

 

The result is that the remaining Cynon, rising in the moors around Penderyn, looks too small to have created the huge valley it runs through, because it is.  All its ancient headstreams now feed the Nedd, the Neath River, which, because it at such a low altitude below Pontneddfechan, barely erodes anything on it's remaining path to the sea at Briton Ferry.  The waterfall streams, in the meantime, continue to cut vigourously into their valleys,

 

My layout is set in a real place that never had a mining village or a railway, though at one time it had a water-wheel powered forge fed by a tramroad, Cwmdimbath, a tributary valley off the Ogwr Fach between Blackmill and Hendreforgan.  It is very much in the mold of the Corrwg, steepsided and narrow, and in reality literally undermined by pits in the neighbouring valleys, but in my alternative reality has a pit, village, and railway.  The pub is called 'The Forge' in honour of the forge that once existed nearby.  The stream is actually called Nant Lechyd.  Should you ever be in the area, the trackbed of the old tramroad makes and easy walk into the hills, the Lechyd burbling away to itself as such streams do, and it is one of the very few places that one can experience the sylvan loveliness that must have characterised all of these Glamorgan valleys before the mining era, which denuded them of trees for pitprops and scarred them with spoil tips.  It is spectacular in autumn.