All that remains of what is believed to be the world’s first integrated slate mill, built in 1859, at Diffwys Casson Quarry in Blaenau Ffestiniog.
The raw blocks of slate were reduced to a manageable size on the right hand side and then transferred to the saw tables down the center of the mill. The splitting and dressing took place along the left hand side of the building and the waste from this process was disposed of to rubbish wagons through the openings on the left. The finished slate left the quarry via an incline which connected to the Ffestiniog Railway.
Words and photo by kind permission of Dave Sallery. For more information from his tremendous website, please click here.