Cefn Mawr, put simply, is the ridge enclosing the north end of an industrial area that developed because of the Pontcycyllte aqueduct, its canal and its tramroads. Tourists who flock to look at the aqueduct rightly marvel at its pedigree as one of the most significant industrial structures in the country. Yet, more than this, it was a catalyst, an agent of change. Ironworks were set up to provide the enormous, high quality castings that Telford and Jessop's bridge required. Collieries were sunk to exploit the local reserves of high quality coal. Stone for building was quarried all along the ridge. Yet, there's surprisingly little to show for all this activity today, apart from the bridge. It's as if there is a collective shame about the signs of early industry, a feeling that it must be swept away out of sight.
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| A ruined farm near one of the coal pits at "The Ballast" |
The excellent booklet, produced by a local community initiative*, goes a very long way to redress the balance. It describes a series of walks not far from the aqueduct with just enough industrial archaeology to enable the visitor with half an imagination to join the dots for him or herself. The Tourist Office carries a dwindling supply of these booklets about the trail, which as far as I can see, is now out of print- a huge shame.
A glance at the Ordnance survey sheet for Cefn Mawr in 1904 will show a bewildering warren of tramroads, plateways, coal mines, foundries and countless other industries, none of which are remotely evident today, save as the odd retaining wall made from furnace slag or an alignment of road or footpath. Oh, for a time machine set at 1860.
And yet, there's something intensely pleasurable in taking in the genius loci, noting with a sudden thrill that the stone wall or abutment you have been looking at is actually one of the vestigial remains of a tramroad or a lime kiln.
Armed with one of the booklets supplied by the very helpful ladies of Trevor Basin TIC, Petra and I chose route D.
I have to say that it was an eye-opener. We walked towards the north end of the Trevor basin, (3) on the map, past the truncated arm of the canal which once served the ironworks. It was an idyllic, bosky scene, and it didn't take much imagination to picture the place as it was a hundred years ago.
Then, the atmosphere changed. A large area of waste land resembling a bomb site opened up behind tall security railings on our right. High masts supported security cameras and lights, guarding the ransacked land where stunted, blighted birches and conifers were struggling to grow.
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| A far view of the Monsanto site from atop the Cefn Mawr ridge. Our route took us immediately in front of the tree line in the middle distance. The Vale of Llangollen is in the far background, and the aqueduct is just out of the photo to the left distance. |
This was the Plas Kynaston estate, where several important industries sprang up in the 1800's to service the construction of the aqueduct. There were brickworks, potteries, engineering works, foundries and, notably, a chemical works which eventually grew to engulf the whole estate. Robert Graesser started an oil works here in the late 1860's to extract paraffin oil and wax from mining waste, later coal tar and explosives. He became so successful that he formed a partnership with the American chemical giant Monsanto. There were changes in ownership later to Flexsys, who closed most of the site and swept away the structures (and any remaining archaeology) but it has since been impossible to develop the area because of the very heavy chemical ground pollution.
There have been several plans mooted. The Plas Kynaston Canal Group want to re-open the canal and build a marina. Others suggest capping the site with concrete and building much-needed houses. There was even a suggestion that development could be funded by extracting the vast mineral wealth that supposedly lies below the site, although I don't see a modern quarry sitting well in a world heritage zone.
Putting those questions aside, we walked on, realising that the embankment to our left was the alignment of the Pontcycyllte Tramroad, a horse-drawn operation, later converted to accommodate steam locomotives. It eventually linked with the railway line to Llangollen, and some bridge abutments could be seen just before the A539 Llangollen Road. Along here on the left was once the mighty Trefynant Fireclay Works, owned by J.C.Edwards, who once supplied glazed terracotta bricks and tiles to the world. Edwards bricks decorated the Natural History Museum in London, as well as the fireplaces on the Titanic! The still new-looking produce of the factory can be seen all through Cefn Mawr as many houses and shops are decorated with the shiny red bricks, made from local clay and fired with local coal.
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| photo: Petra Brown |
We had to cross the A539 Llangollen Road, noting the Trefynant Pottery manager's house, built entirely from Terracotta bricks and tiles.
Once across the road, we took a public footpath alongside a stream, where informal gardens adjoined the opposite bank, Their walls were made from an impressive jumble of different tiles and bricks, something we would become used to seeing on our walk. Tiles marked "J.C.E" lay on the ground or half-buried everywhere along the path, as it passed the disturbed ground and overgrown tips of an old colliery, masked by woodland.
A tunnel was reached, under the disused Ruabon to Barmouth railway, closed in 1965. This is known locally as the "Darkie", as is the tunnel on the south end of the Pontcysyllte aqueduct.
Once out of the tunnel, we encountered an old ruined building, half constructed in Sandstone and half in JCE bricks. Many structures in Cefn Mawr bear the marks of later alterations with local bricks like this. According to the booklet, this was a place known as the "Ballast", an open area pock-marked with vestiges of old pits, shafts and tips. We emerged into a beautiful meadow with many different species of wild flowers which Petra took delight in identifying. Some Vanner ponies were watching us from the top of a low spoil tip, but they must have known that we didn't have any sugar cubes or carrots, as to my disappointment, they kept their distance.
We carried on and emerged, via some giant Lego bricks, into Bowers Road.
Bryn Terrace, seen in the above photo, was built in 1906 from...J.C. Edwards terracotta bricks. Bowers road was rather interesting in that we encountered some bridge abutments that looked to date from the mid-C19th. Later, when browsing early maps of the site, I discovered a reference to the road on an 1880 edition that had a tramroad from the Acre House colliery over the road to a tipping ground on the "Ballast". This area of Cefn Mawr is Acrefair and I wondered if the name came from Acre House farm nearby.
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The Bowers Road tramway bridge abutments. Above the wall is a new road which, looking at Google Earth, obviously takes the line of the tramway formation. We carried on, following the booklet's map and found ourselves at the A539 again. There was once a large railway bridge at the junction, supporting the Ruabon to Llangollen Railway's line. This was removed in the 1960's. The nature of development here felt quite English; the houses for the most part made from local glazed brick with tile embellishments.
Our route now took us onto King street, where I spotted a likely sign...
Which led to this...
At first, I thought it might be an old station or a goods shed, but I realised that it was on the wrong alignment...the GWR line runs North West through here and this is slightly East North East. Looking at the booklet, it could be on the alignment of the GWR Pontcysyllte branch...I wonder...the two lines intersected not far from here, the GWR Llangollen line crossing by a bridge over the Pontcysyllte.
We carried on to High Street, where there were more tiled and glazed brick homes. As the road gained height, stone buildings started to predominate, obviously settlement was older here, pre-dating the tile works. The structures were quite haphazardly built, too, few being square in plan, as if they were fitting into a plot. Many houses date back to when squatters were allowed to build their own homes here on the common land. Gradually, plots became fewer and increasingly odd shaped structures developed. We saw a few with dates like "1760" on the door lintels.
We reached the site of the Zion Chapel, where another mystery reared it's head.I can find no photos of this building before it was demolished, only references to members of the congregation in parish records. A memorial plaque on the wall behind the new house gives the date "1805". Behind, a memorial garden has been built, giving superb views out over the Plas Kynaston site to the Vale of Llangollen. There are some very fine tombstones in the cemetery; unfortunately the only seat has succumbed to the elements, so we perched on a wall to consume lunch, thinking of all those people buried here and what stories they could tell.
A little further along High street and we found the very fine building that is the former Grosvenor Inn.
The booklet recommended taking one of the many alleys and narrow wynds that abound here, down to King Street, where I had a sudden revelation. I realised that King Street was actually built on the alignment of the Pontcysyllte tramway, which would join with the "main line" at Acrefair. I don't think I would have understood this but for the excellent map in the booklet. The pathway was certainly narrow and steep.
We emerged into an area known as "The Crane", pretty much the centre of Cefn Mawr, where roads converge in a haphazard but determined way. According to the booklet, the post office here is the actual site of "The Crane", which was used for hoisting or transferring waggons from one tramway to another at a different level. Or was it?
A report by Govannon Consultants for CADW suggests:
"At the moment there is no firm evidence even to support the existence of a crane, let alone explain its purpose. There has also been a suggestion that the word ‘crane’ has nothing to do with the railway but is an Anglicization of a local Welsh dialect word, ‘craen’ or ‘y graen’, which means slope."
There are certainly plenty of those about here. We descended a steep one called "American Hill" which felt to me a little like a tramway incline, with a stone base at it's foot.
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| American Hill |
The path was apparently named after a local man who made a large sum of money in the States, then returned and opened a shop. In 1849, perhaps?
The photograph from the nineteen thirties, above, shows "the Crane" site and also the route of King Street and American hill. No wonder we couldn't see any remains of the Plas Kynaston Pottery as we came down the hill - all that development on the left of the photograph is Monsanto Chemicals, where the pottery would have been.
We descended yet another tiny alley and dropped down to Queen Street where we took a trackway back to Trevor Basin, past a mothballed industrial plant, itself built over an old colliery shaft. I get the feeling that, like most post-industrial areas, Cefn Mawr would become more interesting in proportion to the time spent studying it. This time, we discovered more mysteries than we found answers for, but that's the thrill of the chase, isn't it?
"Cefn Mawr and District — Understanding Urban Character" superbly written Cadw Report available as a PDF
* Very many thanks to the
Cefn Mawr, Rhosmedre and Newbridge Community Association Ltd.The Plas Kynaston Canal Group Limited copies of the booklet are available at The Tackle Shop, 5a Crane Street, Cefn Mawr LL14 3AB...thanks Steve!
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