The Ogwen Valley is situated in the north of Gwynedd. Slate has been quarried here since the Medieval period but the industry was developed on an extensive scale from the late eighteenth century onwards by Richard Pennant, Lord Penrhyn, and his heirs. The Penrhyn quarry was managed in the same way that they managed their Jamaican sugar plantations and their enslaved workforce there.
The undertaking was rationalised and mechanised on an extensive scale from the 1780s onwards. Roads were improved, benched quarry-galleries and a water-powered saw-mill for slabs introduced. Harbour facilities at Port Penrhyn near the city of Bangor were also improved and a railway built from the quarry to the sea. All this meant that the quarry grew to be the largest slate quarry in the world by the mid nineteenth century, when it employed 2,750 men, producing 110,368 tons of slate a year. It now covers 225 hectares (556 acres).
The quarry and its innovative railway soon became the focus of visits from travellers and others interested in quarrying from England, France and Prussia. The strongly managerial approach followed by the first Lord Penrhyn and his successors and heirs was the cause of constant friction with the workforce. Many of the quarrymen and their families were content to be settled in small cottages on garden plots built by their employer, such as on Mynydd Llandygai.
Others resented Lord Penrhyn’s attempts to control all aspects of their lives, and created their own settlement on a nearby freehold. This grew into the village, later town, of Bethesda, named after its Congregational chapel.
These social tensions erupted in a bitter labour dispute which went on from 1900 to 1903, for many years the longest in British history, and which was commented on in both the United Kingdom and continental European press.
The quarry settlements have seen little significant change since the end of the nineteenth century, and remain excellent examples of both nucleated and dispersed workers’ communities. Bethesda, laid out along Thomas Telford’s post road (now the A5 road), forms part of many travellers’ route through North Wales.
The Penrhyn family lived in the extravagant neo-Norman Penrhyn castle with its surrounding parkland on the outskirts of Bangor. Today the castle and its immediate surroundings are in the care of the National Trust, and the majority of the parkland is still owned by the estate.
Penrhyn quarry remains in active production, and continues to nurture the long tradition of craft skill which is a feature of the industry, though it has also been in the forefront of research and experimentation into the means by which slate-processing can be mechanised.