Bryn Hafod-y-wern Slate Quarry
|Date||5 March 2011|
|Location||Bryn Hafod-y-wern, Llanllechid||SH 63219 69223; 53.20242°N, 4.04926°W|
The quarry was operated by the Pennant family from the 1780s. The lease passed out of the hands of the Penrhyn estate in the 1820s and the Royal Bangor Slate Company, established in London in 1845, later took over. Plans to connect the quarry to the Chester-Holyhead railway at Abergwyngregyn came to nothing, and the quarry was also affected by industrial unrest in the 1880s. Water to power the quarry came from Cwm Caseg via a leat five miles long. The water supply was cut off in 1889.
The hazardous flooded quarry pit is 50m deep and contains dumped unexploded World War II bombs and barbed wire. It is also the grave of a diver who died there in the 1970s.