Old Manod slate quarry is located to the east of Blaenau Ffestiniog. A high altitude open working (>550m) dating from the early 1800s, it appears to have operated without buildings or shelter of any kind. It was later incorporated into the nearby Graig Ddu workings (NPRN 40592) and its remains are not distinguishable from the latter. Much disturbance has also been caused by untopping.
The old track around Mynydd Manod by which material was conveyed to the river Dwyryd is still visible.

Sources:
Ordnance Survey County Series map: sheet Merionethshire IV.10, edition of 1889.
RCAHMW air photos: AP94-CS 0706 & AP945095/46
A.J.Richards, A Gazeteer of the Welsh Slate Industry (1991), p.134.

David Leighton & J.Wiles, RCAHMW, 16 February 2015