Bryn Eglwys quarry

Disused slate quarry in north Wales

Bryn Eglwys quarry was a slate quarry and mine near Abergynolwyn, in Merionethshire (now part of Gwynedd), Wales. More than 300 men worked at the site, making it the principal employer in the area. Two veins of slate, known as the Broad Vein and the Narrow Vein, were worked. The geology continues eastwards towards Corris and Dinas Mawddwy, and westwards towards Tywyn. It was one of many quarries that worked these veins. The site, which was in operation for just over 100 years, covered almost 2 square miles (5 km2). It had several long tunnels up to to However, since closure all buildings have been demolished. Most of its inclines and infrastructure have become part of forestry plantations. From 1866 until closure in 1948, the quarry was served by the narrow gauge Talyllyn Railway, which took the slate down to Tywyn for transfer to the main line railway.

In 1844 John Pugh or Pughe obtained a quarrying lease from Lewis Morris, the owner of the Bryneglwys Estate, for a term of 50 years. Pugh was a local miner from Aberdyfi, who already owned other mines in the locality, including the notable Dylife lead mine, which he owned, in association with Hugh Williams, from 1809 until 1858. In 1846 Pugh obtained another lease, for the Cantrybedd land on the opposite side of the valley. He sank a shaft into the Narrow Vein, which is now known as the Daylight Adit, and built a small mill nearby, which he connected to the foot of the shaft by a level.

In 1863 a group of mill owners from Manchester, led by William McConnel, leased the quarry. Cotton shortages, caused by the American Civil War, had reduced the production of the mills and they were looking for other profitable enterprises. They formed the Aberdovey Slate Company Limited, to operate and manage the quarry, and planned to increase production at Bryn Eglwys. The main barriers to the quarry's expansion at the time were the transportation arrangements for finished slates, and the lack of a workforce near Bryn Eglwys. The new owners overcame the former difficulty by building the Talyllyn Railway, a narrow gauge railway which was designed by James Swinton Spooner. The railway ran from the Cantrybedd incline, which marked the edge of Bryn Eglwys, along the Galltymoelfre Tramway to the Alltwyllt incline, and thence down the Fathew valley to Tywyn, before turning south to reach Aberdyfi. The company built the village of Abergynolwyn to house their workers. In total, the new owners invested around £160,000, , in developing the quarry, building houses for quarrymen in the village of Abergynolwyn and building the railway from the quarry to Tywyn. After this and a subsequent auction failed to find a bidder, William McConnel personally bought both. Nevertheless, McConnel re organised the quarry's finances, and there was then an upturn in the slate market which allowed the quarry to expand further. Haydn Jones’ leases on the quarry land expired in 1941, but he continued to own and operate the quarry, with an annual tenancy. A series of footpaths was created from starting from the Alltwylt Incline and along the Galltymoelfre Tramway, though the path diverges from the Cantrybedd Incline due to a missing bridge.

Three parallel veins of Ordovician slate run through mid Wales, from the region north of Dinas Mawddwy through Corris and south west towards Tywyn. These veins are the southern edge of the Harlech Dome anticline which surfaces in the north at Blaenau Ffestiniog. The Red Vein (also known as the Middle Vein) lies about south of the Broad Vein. It is about 60 feet (18 m) thick but contains low quality, friable slate that contains a large number of fossils. This vein was not worked commercially at Bryn Eglwys. The third vein is the Narrow Vein which lies about south of the Middle Vein and is also about 60 feet (18 m) thick. It contains the highest quality slate of the three veins and the most commercially valuable, being easy to split into roofing slates and slabs and both durable and strong. The vein is mostly a continuous bed of slate, containing only the occasional seam of quartz. However, the quality of the rock varies over the depth of the vein, with the best material being found nearest the surface.