Cwmgwineu Colliery

Overview

A pit at Cwm Duffryn near Port Talbot, its No.1 Pit sunk 604 feet to the Rock Fawr (Wernddu) seam. After decades as little more than a trial working, it grew rapidly in the 1920s to 500 men before closing in December 1927.

History

Cwmgwineu Colliery's No.1 Pit, owned by the Cwmgwyneu Colliery Company of Port Talbot, was sunk to a depth of 604 feet at Cwm Duffryn, finding the Rock Fawr (Wernddu) seam at a section of 40 inches of coal, 6 of dirt and a further 6 of coal. It was shown opening in 1896–99, but for its first quarter century employed only a handful of men — seven in 1899, falling to three by 1900 — and was listed as discontinued by 1905, abandoning the Rock Fach seam in February 1912. The colliery was transformed in the 1920s. By 1922, under the Cwmgwyneu Collieries Company and manager S. Mathews, it employed 152 men on sinking operations; by 1923, now managed by Arthur Richards, it employed 120 men underground and 89 on the surface and was described as "now developing." Manpower then grew sharply: 400 men in 1924–25 and 500 in 1926. The Rock Fawr seam was finally abandoned on the colliery's closure in December 1927, when it still employed 500 men under Richards.

Geology

Worked the Rock Fawr (also called Rock Fach), locally the Wernddu seam, at a section of 40in coal, 6in dirt, 6in coal.

Workings

A single deep pit (No.1), 604 feet, worked in two very different phases: a small trial working to 1912, then a major 1920s redevelopment.

Closure

Closed in December 1927 at the height of its output, employing 500 men, when the Rock Fawr seam was abandoned.

What remains

Unknown.

Nearby mines

• Cwmavon Copper Works — 0.3 km SE
• Ynisdavid Colliery — 1.4 km NE
• Wern Colliery, Cwmafan — 2.9 km NW
• Ynys Dafydd Colliery — 3.7 km NW
• Cefn Parc Arlais Colliery — 3.9 km E

Straight-line distance, within 15 km. Show on the map.

Recorded claims

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

• The No.1 Pit was sunk to 604 feet, finding the Rock Fawr (Wernddu) seam at 40in coal/6in dirt/6in coal; it opened in 1896–99 but employed only a handful of men through to its 1905 discontinuation and 1912 seam abandonment. ^1,2
• Redeveloped from 1922 (152 men sinking), the colliery's workforce grew to 400 men by 1924–25 and 500 by 1926, before closing in December 1927 with the Rock Fawr seam's abandonment, still employing 500 men. ^1,2
• Owned throughout its documented life by the Cwmgwyneu (also spelled Cwmgwineu) Colliery Company of Port Talbot. ²

Photographs & further reading

Sources

1. (secondary) Small Collieries in the Afan Valley and surrounding areas — Northern Mine Research Society
2. (secondary) Cwmgwineu Colliery — Welsh Coal Mines

Record created: 14 September 2026 · Last researched: 15 September 2026