Gilwen Colliery

Overview

An anthracite drift at Cwmtwrch Isaf in the upper Swansea Valley, sunk in 1860 by the Ystalyfera Iron Company, whose locomotives ran from the ironworks over the Patches to it. As an independent colliery in the 20th century it employed up to 400 men, passing to the Globe Collieries and Welsh Anthracite, and abandoned its Red Vein workings in 1927.

History

The Gilwen drift was opened in 1860 by the Ystalyfera Iron Company, which ran locomotives and trams from the ironworks over the Patches by a line known as Railway Fach y Sanau and built an incline to join the railway. In 1881 the company worked it as one of four collieries: 59 people raised 13,409 tons of coal a year from the Big and Brass veins, with 233 tons of ironstone. The Big, Little and Brass seams worked through Gilwen, the Arch, Cwmfelin, Horseway and Mynydd Bach were abandoned by 1882. In the early 20th century the Gilwen Colliery Company of Lower Cwmtwrch worked the slant; in 1908 J. H. Williams managed 210 men underground and 35 at the surface, and in 1913 it employed 309. By 1917 it belonged to the Globe Collieries Company of Cardiff, later absorbed into Welsh Anthracite Collieries. It produced 90,000 tons in 1923 and employed 400 men in 1926 under Thomas Redshaw, who was still manager in 1930 and 1934, when 344 men worked the anthracite. The Old Gilwen, working the Big and Red veins, abandoned the Red Vein in June 1927. Individual deaths recorded at the mine include D. Thomas, killed by a fall of stone in 1874, and in 1909 Gwilym Moses, 18, and George Watkins, 21, thrown from a journey of full drams when a shackle broke.

Geology

Anthracite from the Big, Brass and Little veins, and later the Big and Red veins; ironstone was also raised in the 1880s.

Geological setting: Sedimentary Beds and Seams (historical documentary reference)

Workings

A drift or slant, linked to the Ystalyfera ironworks by the company's own locomotive line over the Patches and an incline to the railway. Local history places it near a disused tip on the edge of woodland above Cwmtwrch.

Closure

The Old Gilwen abandoned the Red Vein in June 1927, and a BGS plan titled Gilwen is dated 1927, but NMRS still records 344 men at Gilwen in 1934. When working finally ended has not been established.

What remains

Unknown.

Unknown.

Redevelopment

Unknown.

Related mines

• Ystalyfera Colliery — Both worked by the Ystalyfera Iron Company, which counted them among its four collieries in 1881.

Nearby mines

• Tirbach Colliery — 1.1 km SE
• Pwllbach Colliery — 1.6 km S
• Ystalyfera Colliery — 1.8 km S
• Hendreforgan Colliery — 2.1 km NW
• Cwmllynfell Colliery — 2.4 km NW

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.

• A drift mine was opened in 1860 by the Ystalyfera Iron Company. ¹
• The Gilwen drift was sunk in 1860; the Ystalyfera company ran locomotives and trams from the ironworks over the Patches by 'Railway Fach y Sanau'. ²
• In 1881 fifty-nine persons in the Gilwen Drift obtained 13,409 tons of coal a year from the Big and Brass veins, and 233 tons of ironstone. ²
• In 1908 the Gilwen Colliery Co. Ltd employed 210 underground and 35 surface workers under manager J. H. Williams. ^2,1
• By 1917 it belonged to the Globe Collieries Company of Cardiff, later absorbed into Welsh Anthracite Collieries Limited, which owned it in 1930. ¹
• Manpower 309 (1913), 300 (1915-16), 123 (1918), 90,000 tons in 1923, 400 (1926), 344 (1930 and 1934). ¹
• A Mining Remediation Authority abandonment plan titled 'Gilwen' (catalogue 9034) records the Red seam, abandoned in 1927, matching NMRS's June 1927 abandonment of the Red Vein. ^1,3
• A plan for 'Gilwen / Arch / Cwmfelin / Horseway / Mynydd Bach' in the Little, Big and Brass seams is dated 1882. ⁴
• In 1909 George Watkins, 21, collier at Lower Gilwen Colliery, Cwmtwrch, was thrown off a journey of full drams when a shackle broke and died in Swansea Hospital that night; Gwilym Moses, 18, was killed by a fall of stone at Gilwen Colliery, Llangiwg, the same year. ⁵
• On 26 May 1874 D. Thomas, 25, collier at Gilwen Colliery, Ystalyfera, was killed by a fall of stone. ⁶

Photographs & further reading

Sources

1. (secondary) Gilwen Colliery — Northern Mine Research Society (Ray Lawrence)
2. (secondary) Coal mining in Gwauncaegurwen and Cwmgors and local area (Glyn-Moch Colliery; Ystrad, Glanaman) — Gareth Hicks, GENUKI
3. (primary) BGS / Mining Remediation Authority mine plans: GILWEN — British Geological Survey / Mining Remediation Authority
4. (primary) BGS / Mining Remediation Authority mine plans: GILWEN /ARCH /CWMFELIN /HORSEWAY/ MYNYDD BACH — British Geological Survey / Mining Remediation Authority
5. (secondary) 1909 fatalities — Welsh Coal Mines
6. (secondary) 1874 fatalities — welshcoalmines.co.uk

Record created: 16 September 2026 · Last researched: 16 September 2026