Dinorwic Quarry was once the second largest slate quarry in the world, next to its neighbouring Penrhyn, which today holds the world's fastest zipline, Velocity at Zipworld.

It is located between Llanberis and Dinorwig in North Wales and covers more than 700 acres of land, dominating the scenery with equally incredible views of Snowdon and Crib Goch mountains.

There are two main sections to the quarry consisting of 40 stepped galleries in total, all of which were joined by a vast internal tramway system.

Today the area is strewn with the remnants of its industrial past and makes for a truly fascinating and educational day out.

Dinorwic Quarry by Westminster Stone | View of Llanberis

The first attempts to mine here started in 1787 and at its peak, Dinorwic slate quarry employed over 3000 men. A huge surge in demand for slate roofing tiles in the late 19th century meant tiles were exported all over the UK, Europe and even Northern America. Production stopped here in 1969, as a result of less demand for traditional building materials and the growing difficulty to extract any more slate from the already sheer rock galleries.

Today, the quarry has a new lease of life, featuring many attractions and activities. It is partly owned by Caernarfonshire County Council who lease it to the National Museum and now permanently houses the National Slate Museum which is situated in the old Victorian workshops.

The museum tells the story of the extensive history of Welsh slate, with workshops designed as if the quarrymen have just left to go home for the night. Talks and demonstrations of the old tools shows insight into how the slate would have been split and worked with. It offers a real interactive insight into the lives of local quarrymen, the disputes, craftsmanship and community.

Dinorwic Quarry by Westminster Stone | View of quarry works towards Snowdon & Crib Goch

Electric Mountain

Part of the disused Dinorwic Quarry is now home to the well known hydroelectric power station ‘Electric Mountain’, construction began in 1974 and was largely welcomed by the community, offering further employment to the area. It opened the gates in 1984 and is regarded as one of the most imaginative engineering and environmental projects of its time.

The project aimed to preserve the natural beauty of Snowdonia National Park by creating hidden tunnels deep within a mountain. Dinorwig power station plays a vital role in supplying Britain with power and mainly operates to help meet peak loads in electricity but also acts as a short term operating reserve which provides a fast response to rapid changes in power demand or the sudden loss of power stations.

Dinorwic Quarry by Westminster Stone | Close Up of Welsh Slate

Dinorwic Quarry Underground

The station consists of 16km of underground tunnels located within the beautiful mountain Elidir Fawr, where 12 million tonnes of stone was removed from inside the already well mined cavern. The site was carefully chosen because Elidir Fawr has a reservoir, Llyn Marchlyn Mawr near the top and Llyn Peris located at the bottom, making it ideal for a pumped storage system. Its construction took ten years to complete and required 1 million tonnes of concrete, 200,000 tonnes of cement and 4,500 tonnes of steel. Today, tours can be taken to explore the caverns and machine rooms further and offer an insight into how hydroelectricity and storage of this energy works.

The scars of the industrial past bare a long, rich history and culture here in North Wales. The deep blue-grey slate sits high among the mountains, looking out towards the Snowdon horseshoe and beyond. A true testament to the resilience of the community and a beautiful display of slate as a traditional building material.


Dinorwic Quarry by Westminster Stone | Slate Wall and Llanberis View

Slate Paving

Westminster stone offer a large range of Slate paving, both natural and hand-made. Our hand-made slate tile ‘Henslate’ is faithfully reproduced from reclaimed slate originals, bringing a timeless weathered and worn appearance to any home. Slate comes in a naturally diverse colour palette that can undertake a range of finishes and cuts, making it a versatile choice for both traditional and contemporary styles. Slate flagstones are very durable and easy to maintain, naturally non-slip they are ideal for patios, paths and steps. Internally, slate tiles can provide dramatic flooring for kitchens, bathrooms, hallways and garden rooms. We also manufacture hand made Yorkstone Paving Slabs at our Shropshire Head Office paving display centre.