Cof Cymru: National Historic Assets of Wales · Wales
Slate Mill
Llanllyfni, Gwynedd, Wales
A Grade II listed building in Pen-yr-Orsedd, Caernarfon, Llanllyfni, Gwynedd, designated on 21 July 2000.
The record
- Designation
- Listed building, Grade II
- Broad class
- Industrial
- Date of designation
- 21 July 2000
- Locality
- Pen-yr-Orsedd
- Town
- Caernarfon
- Community
- Llanllyfni
- Unitary authority
- Gwynedd
- Country
- Wales
- Coordinates
- 53.05990, -4.22683
- Cadw reference
- 23735
Slide toward Today to fade the historical sheet and see the modern map underneath.
David Rumsey Map Collection, Stanford LibrariesDavid Rumsey Map Collection, Stanford LibrariesDavid Rumsey Map Collection, Stanford LibrariesLlyfrgell Genedlaethol Cymru – The National Library of WalesDavid Rumsey Map Collection, Stanford Libraries
5 historical maps cover this location, the earliest the 1795 map "To Sir Watkin Williams-Wynn Bart ... the map of the six counties of North Wales is most humbly inscribed by his obedient humble servant" (Llyfrgell Genedlaethol Cymru – The National Library of Wales).
Historical maps covering this location
- 1795 · To Sir Watkin Williams-Wynn Bart ... the map of the six counties of North Wales is most… (Llyfrgell Genedlaethol Cymru – The National Library of Wales)
- 1883 · Watershed map England, Wales 3. (David Rumsey Map Collection, Stanford Libraries)
- 1896 · Sheet 7. Ordnance Survey of England and Wales. (David Rumsey Map Collection, Stanford Libraries)
- 1899 · 118 Nevin (Hills) (David Rumsey Map Collection, Stanford Libraries)
- 1901 · Sheet 9 and 10. (David Rumsey Map Collection, Stanford Libraries)
Cadw's description
Location
Directly adjoining the slab mill to the south on Level IV (Bonc Isa') of Pen-yr-Orsedd Slate Quarry.
History
Built adjoining the older slab mill in the late 1870s to house 27 De Winton hydraulic feed-saw tables and 26 dressers. At first it was powered by a wire rope transmission from the water-wheel and steam engine power sources in the Level VI mills but after 1906 electric motors were installed in its roof trusses. The slates were removed from the building's roofs c1997. The quarry opened c1816 when it was worked by William Turner. In 1863 it was bought by W A Darbishire & Co., after which it underwent substantial modernisation, reflected in the use of both water and steam power. During the 1890s about 450 men worked here; it finally closed in 1997.
Exterior
Vast rectangular plan slate-slab structure aligned roughly north-west to south-east comprising parallel gable-ended ranges with central valley; the roofs have been entirely stripped of their slates. Doorway roughly in centre of south-west long wall with red brick dressings, raking buttresses and concrete lintel; further entrance in far north-east corner.
Interior
King-post roof trusses throughout, the central roof valley supported on a combination of timber posts and slate-slab piers, the former predominating. The line shafting for the former De Winton hydraulic feed-saw tables survives.
Reason for designation
Included as a well-preserved integrated slate mill (notwithstanding loss of its roof covering), significant in illustrating an important advance in technology and the intensive factory approach to slate processing adopted at Pen-yr-Orsedd; part of the remarkably well-preserved complex of buildings on the site.
Nearby in the register
- Slab MillIndustrialunder 1 mi
- Ropeway Winding House (north-east)Industrialunder 1 mi
- Winding DrumhouseIndustrialunder 1 mi
- Winding Drumhouse and InclineIndustrialunder 1 mi
Other entries of the same register within about three miles of this one, by straight line.