Of the twentieth century and the largest of the quarries at Manod or Madoc Granite Quarry (nprn 537498). It ceased work c.1972, after which much of the quarry floor appears to have been levelled. The extent of the quarry is approximately 200m north by south by 50m wide with a sheer quarry face 30m high on the east side.
Recorded as part of RCAHMW Uplands Initiative Project, R Hayman, H & H, 16/03/2014.

Manod or Madoc Granite Quarry was opened in the late nineteenth century, although it is not depicted on the second- edition of the 25-inch O. S. map published in 1901. 'Granite' was a misnomer; the rock worked for road setts was dolerite. The quarry was served by a siding off the Bala to Blaenau Ffestiniog branch of the Great Western Railway. The quarry was taken over by Cawood Wharton & Co. Ltd. in c1952 and closed c.1972.
W J Crompton, RCAHMW, 21 December 2011.