Cwm Era slate quarry is located on the north side of Cwm Glesyrch in the Dulas valley. An open working, it was started in the 1870s employing about 50 men producing about 600 tons per annum. Work took place on three levels connected by an incline, material trammed to the mill at Esgairceiliog. The site is located in forestry. Almost nothing remains of the quarry itself other than the incline formation and tramway to the mill. The mill complex is intact (in 1991) and in re-use.
Source: A.J.Richards, A Gazeteer of the Welsh Slate Industry (1991), p.184.
