Archive6144120Title94_CS_1002 - RCAHMW Colour Oblique Aerial PhotographsLevelItemDescriptionRCAHMW colour slide oblique aerial photograph of Pen-y-bryn, Quarry, Llanllyfni, taken by C.R. Musson, 02/05/94MediumPhoto.Imagesn
Archive6513744TitleCSAM_MM_2000_10 - Cadw Scheduled Ancient Monument 35mm NegativesLevelSub-groupDescriptionColour photo surveys of scheduled ancient monuments in Caernarfonshire carried out by M.A. Mason, 2000.MediumTwo sheets. Photo.Imagesn
Archive6513747TitleCSAM_MM_2000_13 - Cadw Scheduled Ancient Monument 35mm NegativesLevelSub-groupDescriptionColour photo surveys of scheduled ancient monuments in Caernarfonshire and Anglesey carried out by M.A. Mason, 2000.MediumTwo sheets. Photo.Imagesn
Archive6058526Title8M_3063_1 - Cadw Registered Files CollectionLevelSub-groupDescriptionClosed registered file, ref. no. 8M/3063/1, transferred from Cadw, concerning Penbryn Quarry, Llandwrog, Caerns, vertical steam engine and housing, scheduling. SAM Code CN166 (Descheduled 1973)MediumText.Imagesn
Archive6438463TitleWSP_11 - Welsh Slate Publication CollectionLevelItemDescriptionFigure 78. At Pen y Bryn in Nantlle, water wheels on the hillside powered rod-systems operating the pumps in Twll Balast and Old Pen y Bryn pit. The pumps raised the water to the outflows, which took the water through tunnels to where it emptied into the river on the valley floor to the southMediumGraphic.Imagesy
Archive6438501TitleWSP_49 - Welsh Slate Publication CollectionLevelItemDescriptionFfigur 78. Ym Mhen y Bryn yn Nantlle, pwerai olwynion dwr ar y llechwedd systemau rhodenni a weithredai'r pympiau yn Nhwll Balast ('Pen-y-Bryn Slate Quarry') a'r twll yn y gogledd-orllewin. Codai'r pympiau'r dwr i'r all-lifoedd, a ?i ?'r dwr drwy dwneli i'r man lle y c?i ei ollwng i'r afon ar lawr y dyffryn i'r de. (h) a hawl cronfa ddata Hawlfraint y Goron a Landmark Information Group Ltd (Cedwir pob hawl 2014)MediumGraphic.Imagesy
Archive6144121Title945129_41 - RCAHMW Black and White Oblique Aerial PhotographsLevelItemDescriptionRCAHMW Black and white oblique aerial photograph of Pen-y-bryn, Quarry, Llanllyfni, taken by C.R. Musson, 02/05/94MediumPhoto.Imagesn
Archive6513782TitleCSAM_MM_2003_26 - Cadw Scheduled Ancient Monument 35mm NegativesLevelSub-groupDescriptionColour photo surveys of scheduled ancient monuments in Anglesey and Caernarfonshire carried out by M.A. Mason, 2003-2004.MediumTwo sheets. Photo.Imagesn
