The History of the National Slate Museum

If you ever find yourself in Llanberis, the National Slate Museum is among the first places you should visit. This historical monument pays homage to the over 3000 slate miners that worked in the quarries in Dinorwig in the 19th century.

Before you pay a visit to the museum, here is some history of the museum, the slate mining industry, and some of the highlights you should expect to see on your visit.

The History of Slate Mining in Wales

Slate mining has been a part of the Llanberis community since Roman times. It wasn’t until the beginning of the industrial revolution around 1787 that small scale slate mining started at Dinorwic.

Transportation costs and the Napoleonic wars prevented the mines from their full success. In 1809, a horse-powered tramway was developed. This eased transportation and the mines started flourishing.

At their peak, the slate mines could produce 100,000 tonnes of slate annually and employed over 3,000 men.

Slate mining declined in the 20th century due to a drop in demand and the difficulty of accessing the slate deposits. As a result, the mine in Dinorwig closed in 1969.

The Emergence of the National Slate Museum

The birth of the National Slate Museum was not a one-off event. Instead, it was a series of events that led to the museum.

These events started with the auctioning of the mine’s machinery. With the intervention of the Gwynedd County Council, the workshops at Gilfach Ddu were declared to be of historical value. As a result, the council refused to have the shops sold for development.

The workshops were then used as a home for a museum that would be dedicated to the history of mining in wales.

The quarries, on the other hand, were converted into outdoor activities centres. The workshops that currently house the museum were built in 1870 from land that was recovered from a spil tip in the Vivian Quarry nearby. The narrow gauge railways used to carry slate from the quarries now link the museum to Llanberis village.

Some of the old museum shops are used by the railway to work on locomotives and rolling stock.

The Northern Wales Quarrying Museum

The path of the National Slate Museum hasn’t been the smoothest. The museum first opened its doors to the public on 25th May 1972 as the North Wales Quarrying Museum. On many aspects and sites of this museum, former quarrymen and engineers were employed to present their craft. The equipment used inside the museum was collected from other Welsh Quarries.

The National Slate Museum

What is now known as the National Slate Museum was opened in 1999 after the old museum received a grant from the Heritage Lottery Fund that allowed the museum to be reopened with new features and facilities.

The new museum now featured displays of the Victorian era slate worker’s cottages and a multi-media display that shows the lives and work of the men who mined for slate.

The National Slate Museum is designed to make it feel like the quarrymen just left for the day. As soon as you walk through the door, you get this feeling. It’s laid out like a fort with a high rising clock tower above the central courtyard.

Instead of being a collection of old and dusty regalia, the museum shares a slice of the social mining history of wales.

The most iconic part of the museum has to be the Chief Engineer’s house. This section of the museum was restored to look as it did in 1911. It features steam engines in the locomotive shed, water-powered machinery, forges, and a 19th-century brass foundry.

Main Attractions inside the National Slate Museum

The museum is not short of surprises. One of the reasons it has maintained its status as a must-see in Wales is its extensive collection of historical pieces and information.

The largest Waterwheel on Mainland Britain

You can’t miss the waterwheel inside the museum. It’s the biggest one in mainland Britain. The wheel was built in the 19th century by the Victorian Industrialists, particularly by the De Winton Company of Caernarfon.

The 15.4-metres in diameter wheel was built in 1870. The water to power the wheel was piped down from the slopes of Snowdon using cast iron pipes. The power harvested from the wheel helped in the production of slates for roofs all over Industrial Britain. The wheel was a huge success and remained in operation until 1925 when a smaller and more efficient model replaced it.

Iron and brass foundry

The highest room in the museum is 9.5 metres high and houses the furnace, jib, and the crane. It was once used as an iron and brass foundry. But if you visit today, you can only see the brass furnace. Despite the missing equipment, this is still an amazing part of the museum to see.

Restored cottages

Your tour around the museum is not complete without seeing how the quarrymen lived at the height of the slate mining industry. A set of four restored cottages paints a vivid picture of how the men and their families lived during these times.

Originally, the cottages were near Blaenau Ffestiniog but were carefully disassembled and brought to Llanberis, where they were reassembled on the museum site. To make the picture even clearer, one of the houses was furnished as it would have been in 1861, the other is 1901 themed and a third one as it would have appeared in 1969. The fourth house is saved for interactive learning for children, their families, and schools.


The National Slate Museum is not only a must-see attraction but also a custodian of the history of slate mining in wales. It has numerous features and equipment that explain how vital slate mining was for the region in the 19th century and, most importantly, how the miners lived.

The museum stands as a reminder of the 3000 men that worked inside the quarries as well as some of their work, some of which lie open on the side of the Elidir Mountain.