Wernlas Colliery

Overview

A level at Pentrebach, south of Merthyr Tydfil, opened in 1902 by the small Wernlas Coal Company. It passed to Hill's Plymouth Company and then Sir David Llewellyn's Llewellyn (Plymouth) Limited, employing up to 160 men in the 1920s, and abandoned its seams in 1935.

History

Wernlas Colliery, also recorded as Wernlas Level at the Graig pits, lay at Pentrebach on the east side of the Taff valley south of Merthyr Tydfil. It was opened in 1902 by the Wernlas Coal Company of Abercanaid, a small firm outside the coal owners' association, which employed 3 men in 1903, 18 in 1908 under Evan Jones and 26 in 1913-16. In 1916 a repairer, Richard Morris, 34, was killed by a fall of stone while helping to clear a fall.

By 1918 it was owned by T. W. Rees of Merthyr Tydfil and employed 74 men. In 1923 Hill's Plymouth Company, owners of the neighbouring Graig and Duffryn collieries, had it, with 133 men underground and 27 at the surface under H. P. Jones, and in 1927, as Hill's (Llewellyn) Company, 150. It employed about 100 in 1931-33 and was closed temporarily in 1933. By 1935 it belonged to Llewellyn (Plymouth) Limited, Sir David R. Llewellyn's company run from the South Duffryn colliery office, with 65 men underground and 15 at the surface producing steam coal under T. Jones. That year it abandoned the Upper Two-Feet-Nine, Nine-Feet and Upper Four-Feet seams; its abandonment plan includes workings reached from Duffryn North and the Forge No. 2.

Geology

Steam coal from the Upper Two-Feet-Nine, Nine-Feet and Upper Four-Feet seams.

Workings

A level (drift) at the Graig pits, its later workings joined with those of Duffryn North and the Forge No. 2.

Closure

Closed temporarily in 1933 and abandoned its Upper Two-Feet-Nine, Nine-Feet and Upper Four-Feet seams in 1935 under Llewellyn (Plymouth) Limited.

What remains

Unknown.

Redevelopment

Unknown.

Related mines

• Graig Colliery, Pentrebach — Coflein records Wernlas Level at the Graig pits; both later Hill's Plymouth Company's.

Recorded claims

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

• Wernlas Colliery was opened in 1902 by the Wernlas Coal Company. ¹
• In 1923 Hill's Plymouth Company employed 160 men there. ¹
• A repairer, Richard Morris, was killed by a fall of stone in 1916. ²
• It abandoned the Upper Two-Feet-Nine, Nine-Feet and Upper Four-Feet seams in 1935. ^1,3
• The level is recorded as Wernlas Level at the Graig pits, Pentrebach. ^4,5

Photographs & further reading

Sources

1. (secondary) NMRS: Wernlas Colliery — Northern Mine Research Society
2. (secondary) 1916 fatalities — Welsh Coal Mines
3. (primary) BGS / Mining Remediation Authority mine plan: WERNLAS (including workings from Duffryn North / Forge No 2; Upper Two Feet Nine / Upper Four Feet, abandoned 1935) — British Geological Survey
4. (primary) BGS / Mining Remediation Authority mine plan: WERNLAS LEVEL / NO 1 GRAIG / PENYDARREN NO 1 & NO 2 (Two Feet Nine) — British Geological Survey
5. (secondary) Coflein: Wernlas Level (Graig Pits) (NPRN 33542) — Royal Commission on the Ancient and Historical Monuments of Wales

Record created: 11 October 2026 · Last researched: 11 October 2026