Wynne Quarry

Overview

A slate quarry and mine on the east side of Glyn Ceiriog, a hillside working from about 1770, redeveloped in the 1870s and worked underground from about 1890, with an incline down to the Glyn Valley Tramway. At its peak it made about 2,000 tons a year with 70 men. It closed in 1920 or 1928, and was later a show mine until 1996.

History

Wynne quarry lies on the immediate east side of Glyn Ceiriog, on the north side of Quarry Road. It began as a hillside working in about 1770, was developed further in the 1870s, and from about 1890 was worked underground, in chambers on three levels. The first mill buildings stood close together, with an incline down to the Glyn Valley Tramway; the mill was driven by water, material was raised by steam haulage, and waste was lifted by a water balance. An adit and mill were later built at a lower level, and after the Cambrian amalgamation a Pelton wheel was put in to drive a generator and compressor. In 1898 the quarry employed 64 men, and at its peak in the early 1900s it produced about 2,000 tons a year with 70.

Coflein dates its closure to 1920. Buddlepit's account has it closing first in 1905, reopening briefly in 1910 and 1923 with oil engines driving the mill and compressor, and closing for good in 1928, the date on the last abandonment plans of the Wynne slate workings. The chambers were afterwards used for military storage in the Second World War and as a public water supply until 1952, and from the 1970s were opened to the public as a show mine. An explorer who visited in 2025 found that the attraction had closed in 1996 and that most of its museum displays had rotted away.

Geology

Unknown.

Workings

A hillside quarry, then underground chambers on three levels; a water-powered mill with an incline to the Glyn Valley Tramway; steam haulage and a water balance for waste; later a lower adit and mill, and a Pelton wheel driving a generator and compressor; oil engines in the 1910 and 1923 reopenings.

Closure

Coflein gives 1920; Buddlepit has closures in 1905 and, after brief reopenings in 1910 and 1923, finally in 1928, the year of the BGS abandonment plans.

What remains

Chambers survive on the middle level and the lowest level is mostly flooded; the show-mine displays had largely rotted away by 2025.

On the upper site several buildings survive, including a drumhouse, with traces of the wheel pit, exit incline, water-balance route, a later gravity incline and a cut-and-cover tunnel. The lower site has been largely cleared and is a car park, and the adit is sealed.

Redevelopment

Military storage in the Second World War, a public water supply until 1952, and a show mine from the 1970s until 1996.

Related mines

• Cambrian Quarry — The two slate quarries of Glyn Ceiriog, both served by the Glyn Valley Tramway.

What's uncertain

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

• The quarry and mine closed in 1920. (disputed) ^1,3
• The quarry closed in 1905, reopened briefly in 1910 and 1923, and closed finally in 1928. (disputed) ^2,4

Recorded claims

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

• Wynne began as a hillside quarry in about 1770, was developed in the 1870s and worked underground from about 1890. ^1,2
• In 1898 the quarry employed 64 men; output peaked at about 2,000 tons a year with 70 men. ^1,2
• The quarry and mine closed in 1920. (disputed) ^1,3
• The quarry closed in 1905, reopened briefly in 1910 and 1923, and closed finally in 1928. (disputed) ^2,4
• The workings were later used for military storage and opened to the public from the 1970s. ^1,2

Photographs & further reading

Sources

1. (secondary) Wynne Slate Quarry (NPRN 420115) — Coflein (RCAHMW)
2. (secondary) Wynne (Chwarel Wynne) — Buddlepit Mine Database
3. (observational) Chwarel Wynne Slate Mine - Glyn Ceiriog, Llangollen - June 2025 — 28DaysLater
4. (primary) BGS mine plan: Wynne, slate, abandoned 25 January 1928 — BGS / Mining Remediation Authority mine plans

Record created: 4 October 2026 · Last researched: 4 October 2026