Mynachdy Colliery in Ynysybwl opened at this location in 1903 slightly to the north of earlier, abandoned workings (Grid Ref: ST0492794703) which were worked, intermittently, from the 1870s to the 1890s. The mine was finally closed in 1943 and never worked again. The lack of profitability and the small numbers of men who worked there ensured the turbulent history of this colliery.Now hidden in the undergrowth, aspects of this colliery still survive including the powdershed with the worn stonework where barrels of powder would once have rested. Ruins of the former stable block are also apparent.

Daryl Leeworthy, RCAHMW, 17 October 2011.