Bryneglwys Slate Quarry

There is another band of Ordovician slate further south than Blaenau Ffestiniog, running from Llangynnog to Aberdyfi, quarried mainly in the Corris area. Bryneglwys was the largest producer in this area, producing about 30% of the slate from the area. But was still small with an anuall peak output of around 6000 tons compared to the 100,000 plus tons of Penrhyn. Along with Bryneglwys there were other quarries like Aberllefenni and Abercorris

Slate was first quarried at Bryneglwys Slate Quarry, near Abergynolwyn, Merionethshire, in the 1840s by John Pughe of Aberdyfi. Oddly the American Civil War was the reason for the construction of a railway to serve the quarry. The Aberdovey Slate Company Limited was formed in 1864 by William McConnell to lease the quarry and open it up on a large scale. McConnell was the owner of a Manchester cotton mill and wished to diversify his interests because of the shortage of raw cotton due to the war in America.

The limiting factor to large scale production was that finished slates had to be taken by pack horse to the wharves at Aberdovey. To speed this up, William McConnell built the Talyllyn Railway, a narrow gauge line running 7.25 miles from the quarry to the coast at Tywyn, Merionethshire, where slate could be transhipped to the newly built Aberystwyth and Welsh Coast Railway. The railway ran to Nant Gwernol, a lonely spot about 430 feet below the main quarry level. From there a series of inclines rose to the quarry.

At Nant Gwernol the line is 270 feet above sea level; the quarries are at almost 700 ft. Beyond the first (Alltwyllt) incline was the half-mile long Galltymoelfre tramway, worked by horses, then the Cantrybedd incline lifted the tracks further to the lowest level of the quarry and eventually, via Beudynewydd incline and a further horse-worked tramway the line reached the main quarry buildings.

The Talyllyn Railway Company was formed through an Act of Parliament and the railway was completed in about 1865. The Talyllyn Railway was the world's first narrow gauge railway to be built expressly for steam engines, and provided a freight and passenger service.

Neither the quarry nor its associated railway were great commercial successes. By 1879 the company had run out of funds and both were auctioned off on 9th. October of that year. After this and a subsequent auction failed to find a bidder, William McConnell personally bought both for £18,000 and an upturn in the slate market allowed the quarry to expand further, with a large new mill on Cantrybedd level and new underground levels and chambers.

Bryneglwys grew to be one of the largest quarries in mid Wales, employing 300 men and producing 30% of the total output of the Corris district. Nevertheless it was only producing 5000 to 6000 tons of slate per year at its peak.

McConnell died in 1902 and the quarry became the property of his son W.H. McConnell. However the leases on the land the quarry occupied were close to running out and Bryn Eglwys ceased production in 1909 because due to the quarrying of all the best rock and the lack of capital investment for many years it was in decline. On 17th December 1909 the men were told that the quarry was to close the next day. The remaining stocks were sent down the railway, and the machinery began to be dismantled.

Sir Henry Haydn Jones (1863-1950) was one of the longest serving Liberal Members of Parliament representing a Welsh constituency at Westminster, during the twentieth century, apart from David Lloyd George. As a newly elected M.P., Haydn Jones’s attempted to find a buyer for the Abergynolwyn Quarry, but with no success. In January 1911, he decided to himself buy the quarry, village and the Tal-y-llyn Railway for £5250 using borrowed capital. Before the end of the year, the Abergynolwyn Slate and Slab Company Limited had been formed with Haydn Jones as sole director.

Production then continued until in 1917 slate quarrying was declared a non-essential industry and one can see that employment dropped suddenly at Bryn Eglwys until the end of the war.

Production at Abergynolwyn only picked up slowly after World War I, with 1919 and 1920 production only half the immediate pre-war levels. The quarry remained open only by cutting away at the pillars separating the underground chambers, a cheap alternative to opening up new chambers and levels. Relations between Haydn Jones and the quarrymen were occasionally strained, and at times the quarry closed for considerable periods or worked only a three-day week. In December 1939 there was a serious cave in, but fortunately without loss of life.

Haydn Jones' leases on the quarry land expired in 1941, though he continued with an annual tenancy. The quarry finally closed following a serious collapse on Boxing Day 1946, the inevitable result of years of "pillaring". After the remaining slate had been brought down, the quarry lay abandoned for several years before the equipment was scrapped. All the buildings on the site have now been demolished, for safety reasons.

The Tal-y-llyn Railway first opened in 1865 still continues to run as a tourist attraction.


A book about the Bryneglwys Slate Quarry has been published. This book, written by a Talyllyn Railway Preservation Society member Alan Holmes, is a comprehensive history of the quarry operations and its association with the railway. The book is a fitting tribute to the quarry and the quarrymen. Holmes reports anecdotal evidence that Haydn Jones, the Bryneglwys slate quarry lessee 1911–1946, drove the adit in the hope of finding manganese. When work in the quarry was slack, a couple of men would be sent there to extract some material but Homes does not believe any useful manganese was ever found.

Today, much of the quarry is hidden under forestry work and vegetation and the buildings were 'lost' some years back.

Photograph of the buildings in the early 1960's before demolition
In the early 2000's with the forests

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Welsh Slate Quarries