Gadair Wyllt Slate Quarry

Overview

A small slate quarry above Llyn y Gader near Rhyd Ddu, worked from about 1885 to 1920, stopped and restarted through the First World War and reopened once more in 1919.

History

Gadair Wyllt (Gader Wyllt) quarry lies on the slope above Llyn y Gader, south of Rhyd Ddu at the head of the Gwyrfai valley. It is shown as Gader-Wyllt Slate Quarry on the first edition of the Ordnance Survey map, and is said to have worked from about 1885 to 1920. Slate was carried away along a causeway that is now the Lôn Gwyrfai path between Rhyd Ddu and Beddgelert, and for a time the quarry's waste was tipped into the lake.

The First World War stopped it more than once. In October 1914 Gader Wyllt and the larger Glanrafon quarry were working only three days a week, and by the end of November both had stopped, leaving every quarry and mine in Beddgelert parish idle and sending men to the South Wales collieries. In February 1915 a number of men from Beddgelert and Rhyd Ddu went back to work at Gader Wyllt, where there was said to be a great demand for the slates. A Rhyd Ddu correspondent wrote in October 1916 that the manager had opened a new quarry at Gader Wyllt which had already produced thousands of coloured slates, but that it too had been stopped by the war and the lack of demand. In October 1919 the quarry was being reopened, with Cadwaladr Humphreys, a county councillor, as manager.

Geology

Unknown.

Workings

Two open pits: a smaller one about 50 m long, 15 m wide and 4 m deep, and a larger one about 40 m by 20 m and 14 m deep to the south of the main spoil heap.

Closure

Stopped in late 1914, restarted in 1915, stopped again during the war and reopened in 1919; it is said to have closed about 1920.

What remains

Spoil heaps, the two pits and ruined buildings remain above the lake; a row of slate pillars stands among the waste beside the Lôn Gwyrfai path.

A spoil heap about 110 m long and 8 m high with a length of narrow-gauge rail and a building on top, an open-sided building, scattered building foundations, and the causeway that carried the slate.

Redevelopment

The causeway is now part of the Lôn Gwyrfai multi-user path between Rhyd Ddu and Beddgelert.

Related mines

• Glanrafon Quarry — Neighbouring Rhyd Ddu slate quarries, stopped together in late 1914.

What's uncertain

Points where sources disagree or the record could not be settled; both accounts are kept. All open questions in the archive.

• Gadair-wyllt quarry was operational between 1885 and 1920. (uncertain) ¹
• The Lôn Gwyrfai path between Rhyd Ddu and Beddgelert follows a causeway originally used to carry slate from the quarry. (uncertain) ³

Recorded claims

Individual factual claims, each attached to the source(s) that support it below. Where sources disagree, both are kept.

• Gadair-wyllt quarry was operational between 1885 and 1920. (uncertain) ¹
• The quarry has a pit about 50 m long, 15 m wide and 4 m deep, and a larger pit about 40 m by 20 m and 14 m deep, with a spoil heap 110 m long. ²
• The Lôn Gwyrfai path between Rhyd Ddu and Beddgelert follows a causeway originally used to carry slate from the quarry. (uncertain) ³
• In October 1914 Gader Wyllt and Glanrafon quarries were working only three days a week, and both had stopped by the end of November 1914. ^4,5,6
• In February 1915 men from Beddgelert and Rhyd Ddu restarted work at Gader Wyllt quarry. ⁷
• By October 1916 a new working at Gader Wyllt had produced thousands of coloured slates before being stopped by the war and the lack of demand. ⁸
• In October 1919 the Gader Wyllt quarry was being reopened with Cadwaladr Humphreys as manager. ⁹

Sources

1. (observational) Gadair-wyllt Quarry (Geograph 4035583) — Geograph Britain and Ireland
2. (secondary) Gader-Wyllt Slate Quarry (NPRN 287213) — Coflein (RCAHMW)
3. (observational) Lôn Gwyrfai Path (Geograph 4039499) — Geograph Britain and Ireland
4. (primary) Y Genedl, 20 October 1914: Beddgelert — Y Genedl (Welsh Newspapers Online, National Library of Wales)
5. (primary) Baner ac Amserau Cymru, 5 December 1914: Beddgelert — Baner ac Amserau Cymru (Welsh Newspapers Online, National Library of Wales)
6. (primary) Yr Herald Cymraeg, 1 December 1914: Colofn Carneddog — Yr Herald Cymraeg (Welsh Newspapers Online, National Library of Wales)
7. (primary) Y Genedl, 9 February 1915: Beddgelert — Y Genedl (Welsh Newspapers Online, National Library of Wales)
8. (primary) Yr Herald Cymraeg, 17 October 1916: Rhyd-ddu — Yr Herald Cymraeg (Welsh Newspapers Online, National Library of Wales)
9. (primary) The Cambrian News and Merionethshire Standard, 3 October 1919: Portmadoc — The Cambrian News and Merionethshire Standard (Welsh Newspapers Online, National Library of Wales)

Record created: 20 October 2026 · Last researched: 20 October 2026