Even in the mountainous regions of the country it is still common to find traces of industrial heritage. What we think of as wild spaces were not always so, and amongst the many different landscape uses North Wales has seen, one of the major industries to affect the mountains was the mining and quarrying of slate.

Slate is mudstone that has been compressed, orienting the rock crystals in such a way that is can be split into sheets. These sheets can be used for everything from flooring tiles to ornaments, but historically the major use they have had is as roofing material. Though slate has been mined in Wales for hundreds of years, it became a massive industry from the 18th to 20th centuries, changing the landscape and setting a course for that part of the country that is still being felt today.

Walk through many hills in Snowdonia and you will come across the remnants of slate mines. In fact, it is difficult to go on a walk there and not come across something from this industry. The most obvious remains on the surface are the spoil tips; heaps of abandoned waste that were left to form their own mini hills down the mountainside. There are enormous examples of these at the largest slate quarries, next to Llanberis, Bethesda and Blaenau Ffestiniog, but there are hundreds of smaller ones beneath mine entrances up in the hills.

Alongside these spoil tips you can see the infrastructure. The walls and chimneys, also built out of slate, are well preserved in places, the only distinctive loss being their roofs. Set apart from these mine building are rows of square houses where the workers used to live, and you can see good examples of these high in the Moelwyns. The buildings are also easy to spot if you head up Snowdon from the south, via the Watkin path or the south ridge.

Though it can be hard to feel comfortable with heavy industry in one of our most stunning mountain areas, slate mining brought a huge economic boom to the area, enabling the development of many of the towns we visit as walkers, and many of the roads we drive along. The famous road down the Ogwen Valley was built with slate money, and many of the old inns and hotels were built by the same patrons, to welcome the first tourists to the area well after slate had become an established industry.

At it's height towards the end of the 19th century, the slate from Wales was shipped throughout the world, and changed the fortunes of Snowdonia. Walking in the hills these days it is not uncommon to see old spoil tips being slowly overgrown by vegetation and disappearing back into the landscape, even while other quarries are put to different uses, such as the world class slate climbing that goes on near Llanberis and the tours of underground caverns in Blaenau Ffestiniog.

Next time you walk in Snowdonia, look out for the signs of the old slate mines in the hills, or take a ride on one of the narrow-gauge railway lines, originally used to transport slate to the coast and now fully reinvigorated for visitors. It is a less well-known story of Britain's past industrial might that has declined over time by competition from other materials and from overseas. And whatever you think of the scars on the landscape, it changed this part of the country for good, and is as much part of the National Park as the mountains and lakes.

Large Outdoors offer a full range or walks, sea kayaking trips and wild swimming adventures in Snowdonia, visit our dedicated Snowdonia page here…