Welsh Slate Quarry Co
The Welsh Slate Co. Quarry was the original quarry opened by Samuel Holland in 1818, and therefore has great historical significance. In 1825 he sold it to the Welsh Slate Co., who promptly started serious underground mining.
It was this quarry which built the viaduct across the road/LNWR line (the right hand support column of which can still be seen today) in an attempt to find more land for the dumping of slate waste. This became the Glan-y-don tip, since removed.
The old viaduct which was a landmark of the Dinas area for a long time. Picture:© Graham Isherwood
The above was an attempt at recreating the fine picture of this in the Bleasdale Photographs.collection
The lowest part of the original quarry was known as Lord Palmerston's Quarry, and this was connected to the Festiniog Railway by an incline in 1838.
The quarry was taken over by W.E. Oakeley in the early 1880s following some collapses which threatened his own quarries, situated above, and it was consequently amalgamated with his Middle (ex-Mathews) and Upper (ex-Holland) quarries. Oakeley had acquired these in 1878 after the leases expired. Prior to the collapses the quarry output was some 34,000 tons, and it employed 720 men.