Lynn Cwmorthin abandoned Slate quarry

Llyn Cwmorthin is a striking mountain lake located in the hanging valley above the village of Tanygrisiau, near Blaenau Ffestiniog in Eryri National Park (Snowdonia), North Wales. The lake sits at an altitude of approximately 325 meters (1,060 feet) and is renowned for its stunning scenery, framed by the historic ruins of the 19th-century slate-mining industry. Cwmorthin quarry was a slate quarry west of the village of Tanygrisiau, north Wales. Quarrying on the site started in 1810. In 1860 it was connected to the Ffestiniog Railway. In 1900 it was acquired by the nearby Oakeley quarry and the two were connected underground. Surrounded by still active quarries near the town of Blaenau Ffestiniog, Cwmorthin sits right in the heartlands of Snowdonia National Park. Cwmorthin dates back to 1810 when it was founded as an offshoot of the nearby Diphwys Casson quarry. Throughout its life, the quarry would see some success but difficulties that combined poor conditions for workers, difficulty expanding the underground chambers efficiently and fluctuations in ownership would eventually lead to its decline. Harsh work, poor ventilation, and the use of underground steam boilers earned the remote site the grim nickname "The Slaughterhouse" due to 21 worker deaths between 1875 and 1893.