Small underground working.*
Publications (3)
- Richards, Alun J. (2013); Slate Quarrying in Wales; Gwasg Carreg Gwalch; ISBN 1-84527-026-6
- Richards, Alun John (1991); Gazeteer of the Welsh Slate Industry, A; Gwasg Carreg Gwalch 978-0863811968
- Richards, Alun John, (1999); The Slate Regions of North and Mid Wales and their Railways; Gwasg Carreg Gwalch; 0863815723
Clogwyn Garw - 457m- Chwarel Llew Twrog - 592m
- Y Garnedd - 633m
Llyn Gamallt - 818m- Chwarel Llew Twrog - 855m
Gamallt - 930m- Manod - 1,005m
- Sarn Helen - 1,026m
- South Pole - 1,142m
- Ffridd - 1,290m
- Frudd - 1,372m
- Graig Ddu - 1,452m
- Carters - 1,455m
- Blaen y Cwm - 1,525m
- Drum - 1,613m
Trial - 1,753m- Nelw Williams Quarry - 1,762m
- Rhiwbach - 1,824m
- Nantpistyll Gwyn - 1,928m
- Foel-Gron - 1,936m
