Brynmawr slate quarry operated intermittently in the 1860s and 1880s; taken over by Cefn-du in 1886. Steam was possibly used for pumping and hauling and product was transported by the Ffridd incline. The site remains consist of nothing other than the pit itself, some buildings, possible vestiges of the steam powered incline and an adit which has been lost in forestry.

Richards, A. 1999. The Slate Regions of North and Mid Wales. Gwasg Carreg Gwalch
RCAHMW AP945131/44, 48
RCAHMW, 2009