Level Fawr Adit Mouth is the longest drainage tunnel in Mid - Wales, draining four mines that were; Penygist (NPRN 91742), Logaulas (NPRN 33890), Glogfach (NPRN 33873) and Glogfawr (NPRN 33874) mines.

The site is marked by an arch of stone with keystone bearing a probable nineteenth century inscription that says, ?This level was commenced A.D. 1785.? The inscription includes crossed miners? picks. The stone rubble retaining wall that surrounds the arch rises to form a parapet with coping to the road above. The tunnel has a vertical step of ten to twelve feet and a sideways offset of four to five feet where the tunnel met the one from Glogfach and Glogfawr. (Ex inf Mike Munro, 64 Garden Suburb, Barry).

Related additional remains include an accounting house where the miners drew their pay (NPRN 33897), a wheel pit at Logaulas and a long leat, wheel pit and dressing floor, all dating from the nineteenth century, survive at Glogfach and Glogfawr.

Claire Parry, RCAHMW, 13 June 2011

SOURCES: Association for Industrial Archaeology: A Guide to the Industrial Archaeology of Mid - Wales, 1984