Britannic Colliery

Overview

The Britannic Merthyr Coal Company's steam-coal pits at the head of the Gilfach Goch valley, with the Llewellyn, North and Trane shafts, part of the Cambrian Combine from 1910 and closed in 1960.

History

Britannic Colliery stood at the head of the valley at Gilfach Goch, on a mineral lease of over 2,000 acres taken by the Dinas Main Coal Company. NMRS gives its opening as about 1873; its Dinas Main page has the company announcing two new pits to the steam coals in November 1893 and raising first coal on 22 April 1895. The Llewellyn Pit, 20 feet across, was sunk to 512 yards, with the North Pit 30 yards away as the upcast; the 15-foot Trane Pit, first sunk to 332 yards in 1887, was deepened to the Four-Feet seam at 462 yards in 1911-12. By about 1900 the owners were the Britannic Merthyr Coal Company, and in 1907 the old Dinas Main pit was merged into Britannic.

In 1910 the company joined D. A. Thomas's Cambrian Combine, and Britannic was drawn into that year's Cambrian dispute: three men were scared off boring holes to blow up the manager's house, and in December a crowd of about 300 attacked a working miner, William Gould, inside a ring of seventeen policemen until he agreed to leave the valley. In 1913 the combine became Consolidated Cambrian Ltd, in 1929 Welsh Associated Collieries, and from 1935 Powell Duffryn Associated Collieries.

Britannic employed 1,079 men in 1923 and 1,180 in 1926, working the Five-Feet, Yard (Bute), Red Vein, Six-Feet, Four-Feet and Pentre seams for prime coking and steam coal. The sinkings cost lives: four men died in an explosion in the Trane Pit in April 1912, and four more at the adjoining Llewellyn sinking in April 1913 (see Disasters, below).

Under the National Coal Board the Trane shaft was used to raise Britannic's coal; the Trane Pit stopped production in November 1953 when its Pentre seam was exhausted. Britannic closed on 30 January 1960, its men moving to the new Cwm and Coedely combine.

Geology

South Wales Coal Measures, steam and prime coking coals: the Five-Feet (66 in), Yard or Bute (60 in), Red Vein or Lower Nine-Feet (60 in), Upper Nine-Feet called the Six-Feet (74 in), Lower Six-Feet called the Four-Feet (63 in), and the Pentre (33-39 in).

Workings

The Llewellyn Pit (20 ft, 512 yards) and the North Pit upcast, 30 yards apart; the Trane Pit (15 ft, sunk to 332 yards in 1887 and to 462 yards in 1911-12), which worked the Pentre from a landing at 200 yards. At closure three seams were worked from the Llewellyn Pit with compressed-air machinery.

Closure

The Trane Pit stopped production in November 1953 on exhaustion of the Pentre seam. The National Coal Board closed Britannic on 30 January 1960 and transferred its men to the Cwm and Coedely combine.

What remains

Unknown.

Redevelopment

Unknown.

Related mines

• Dinas Main Colliery — Sunk by the Dinas Main Coal Company, which became the Britannic Merthyr Coal Company; the Dinas Main pit was merged into Britannic in 1907.

Disasters & major incidents

• Trane Pit shaft explosion, 1912
  17 April 1912 · Explosion · 4 fatalities
  At about six on the morning of Wednesday 17 April 1912 firedamp exploded in the Trane Pit at Gilfach Goch, just deepened by the Cambrian Combine, while men on a staging 40 yards down were walling the mouth of a new fan drift. Four were killed and three burned. The inquest blamed a sinker's pipe.
• Britannic Colliery Llewellyn Pit shaft accident, 1913
  27 April 1913 · Winding / Shaft Accident · 4 fatalities
  At about 1.45 p.m. on Sunday 27 April 1913 the side of the new Llewellyn sinking at Gilfach Goch, beside the Trane Pit, gave way and swept seven men off their staging into the flooded sump. Four were drowned. The mechanical engineer Thomas Thomas went down on a rope and brought the other three out, for which the King decorated him.

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 mine was opened around 1873 by the Dinas Main Coal Company with a mineral lease of over 2,000 acres. (disputed) ¹
• In November 1893 the Dinas Main Colliery was to sink two new pits to the steam coal seams (the Britannic Pits); the first coal was raised on 22 April 1895. (disputed) ²

Recorded claims

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

• The mine was opened around 1873 by the Dinas Main Coal Company with a mineral lease of over 2,000 acres. (disputed) ¹
• In November 1893 the Dinas Main Colliery was to sink two new pits to the steam coal seams (the Britannic Pits); the first coal was raised on 22 April 1895. (disputed) ²
• The Llewellyn Pit was 20 feet in diameter and sunk to 512 yards, with the North Pit as upcast 30 yards away. ¹
• The 15-foot Trane Pit was sunk in 1887 to 332 yards and deepened between July 1911 and March 1912 to 462 yards, to the Four-Feet seam. ^1,3
• In 1923 Britannic employed 918 underground and 161 on the surface, the Dinas Main Level 247 and 42, and Trane and Llewellyn 538 and 114. ¹
• The colliery was closed by the National Coal Board on 30 January 1960 and the men transferred to the new Cwm/Coedely combine. ¹
• Abandonment plans are catalogued for Britannic, Trane and Llewellyn in the Bute or Upper Five Feet and the Six Feet seams. ^4,5

Photographs & further reading

Sources

1. (secondary) Britannic Merthyr Colliery - Northern Mine Research Society — Northern Mine Research Society
2. (secondary) Dinas Main Colliery - Northern Mine Research Society — Northern Mine Research Society
3. (secondary) Trane Pit - Northern Mine Research Society — Northern Mine Research Society
4. (primary) BGS mine plans: Britannic, Trane and Llewellyn (Bute or Upper Five Feet) — British Geological Survey / Mining Remediation Authority
5. (primary) BGS mine plans: Trane and Llewellyn, Penrhiwfer, Britannic (Six Feet) — British Geological Survey / Mining Remediation Authority

Record created: 2 October 2026 · Last researched: 2 October 2026