Snowdonia Slate Mines

June 25th, 2017

A quiet corner of north Wales holds deep buried secrets to the area’s bustling industrial past

From a distance, the mountains that surround the little town of Blaenau Ffestiniog are breathtaking in their quiet beauty, but dig a little deeper and there is a treasure trove of secrets to unlock; a glimpse of a noisy and destructive industrial era long left behind and an eerie peek into the hard life of a quarry miner in the mid nineteenth century.

Slate was first mined in North Wales as far back as roman times, when the fort at Segontium near Caernarfon was built with local slate. But it was in the nineteenth century that the slate industry really took hold of the area and changed landscapes and communities forever.

As the industrial revolution began to gather speed and more and more demands were placed on natural resources, the tough, resilient nature of slate was recognised as the building material of the future. The slate from North West Wales is reputedly the best in the world; it didn’t take long for once sleepy farmland and quiet hills to succumb to the lure of the grey gold. The Oakley mine near Blaenau Ffestiniog grew to be the largest in the world.

Buried treasure

Just to the west of the town, high in the hills above Tanygrisiau village lies the valley of Cwmorthin. Nestled into the crook of the mountain are the remnants of the valley’s industrious past. Much of the ground workings and site buildings are still visible, which makes this area captivating and eerie all at once. At the peak of slate production there were six mines dotted across the small valley.

Mining began here as far back as the early nineteenth century, although there had been small scale mining at Blaenau Ffestiniog for fifty or so years earlier. The lease to work the land at Cwmorthin was first secured by the Casson family in 1810. “Its fortunes have ebbed and flowed ever since” admits Graham Isherwood in his book Cwmorthin Slate Quarry.

It wasn’t until the mid 1800’s that the mines began to produce decent quantities of slate, when numerous and fractured ownership was followed by heavy investment, which allowed the Cwmorthin Slate Company to build a tramway to transport the slate from the isolated valley down into Tanygrisiau and onto the wagons at the Ffestiniog Railway station.  By the 1870’s, the mine was sending 14,000 tonnes of slate a year to the docks at Porthmadog for export all over the world.

Ghosts of the past

Cwmorthin mine lies at the foot of the valley to the right. At the other end of the lake is the smaller Conglog Mine, and further up at the head of the valley lies the even more remote and desolate Rhosydd Quarry. Nestled on a flat shelf here, in between the mountains of Cnicht and the Moelwyns are the dark grey shells of a half dilapidated village, built for the miners and their families. It is a fragile place that is bleak, eerie and dark.

From wiki commons

What’s left on the surface of the land is a series of terraced barrack houses and buildings, now sadly stripped of anything of value; their nakedness making them seem vulnerable despite their robust slate construction. It’s a place where the wind whistles and ghosts whisper, sombrely quiet as if in respect to its ominous past.

Most working class families in the area had links to one slate mine or another. The mines had poached many farm workers from the industry that had previously made up the area’s main economy. By 1898, there were just over 17,000 men employed in the slate mines of North West Wales.

Life was tough for the miners, and their families who were brave enough to join them. Men trekked up to Rhosydd from Croesor, Penrhyndeudraeth and even Beddgelert to work, and because of the remote location, the barracks were built to house the men from Monday to Saturday. The work was dangerous, living quarters were overcrowded and unhygienic and it was bitterly cold most of the year round. Rhosydd Quarry was known to have the worst working conditions in the area. Life expectancy was perilously low for a quarryman.

In fact, Cwmorthin Mine was locally nicknamed the “Slaughterhouse” because of its incredibly high rate of deaths and injury. Most fatalities were caused by falls – of men from precipices, ledges and bridges or by falling pieces of rock and slate.

Community Spirit

Local folk stories abound of a close knit society at Rhosydd; the long, cold evenings filled with cheap ale, discussion, and debate. The members of the Male Voice Choir from this bleak little place were celebrated throughout the whole area.

The mine at Rhosydd was abandoned by 1930, and the Cwmorthin mine limped on after the Second World War, but closed finally in the 1950’s. This spring the last of the working mines in Blaenau Ffestiniog closed because of safety fears. It seems that this once prosperous and thriving industry along with its people, stories, tales and fables really have been pushed into the history books.

The ruins at Cwmorthin and Rhosydd stand as a testament to the army of men who put this little town on the map and dazzled the world with Wales’ grey gold.

Slate by Numbers

  • Slate was formed between 3 and 400 million years ago
  • The Ffestiniog Railway was finished in 1836 to transport the slate from Blaenau Ffestiniog down to the coast.
  • It took an apprenticeship of 5 years to become a miner.
  • To mine one tonne of quality slate, up to 30 tonnes of waste were produced.
  • Slate tiles were graded in terms of size. A Duchess tile is 24 x 12 inches. A Countess is 20 x 10 inches and a Lady is 16 x 8.
  • In 1793, Wales was producing 26,000 tonnes of slate a year. By the end of the 1870’s, Wales was producing 450,000 tonnes of slate a year.
  • 201 ships were built at Porthmadog between 1836 and 1880 to cope with the demand for transporting Welsh slate across the world.
  • A miner or quarry man earned about 27½ pence a week in 1870, when the average cost of rent was 12½ pence per week and coal was a little more.
  • Between 1862 and 1900 307,170 tonnes of slate left the Cwmorthin mine

Why not try our Cwmorthin Walk – find details here