Coedely Colliery

Overview

A prime coking colliery in the Ely valley. The Welsh Navigation Steam Coal Company — a subsidiary of David Davis and Sons — began sinking two shafts here in 1901 and drew first coal in 1906, going down 701 and 763 yards. It carried coke ovens and a full by-product plant from the start, its coal classed as prime coking coal for foundry and blast-furnace use. Between 1952 and 1960 it was joined underground to Cwm Colliery over five kilometres east, and the pair became the largest colliery in the South Wales coalfield. It closed on 28 November 1986, the same day as Cwm.

History

The Welsh Navigation Steam Coal Co. Ltd began sinking the two shafts at Coedely in 1901, the first coal being produced in 1906. The company, a subsidiary of David Davis and Sons Ltd, was incorporated in 1906 with its headquarters at Cambrian Buildings, Cardiff, and joined the Monmouthshire and South Wales Coal Owners Association. It sank the No. 1 pit to 701 yards and the No. 2 to 763 yards, the shafts 40 yards apart and both 20 feet in diameter, and equipped the colliery with coke ovens and a complete by-product plant. The workforce numbered 231 in 1908 and 1,450 by 1918. A list of 1923 records 467 men at the No. 1 pit working the Four Feet seam and 1,049 at the No. 2 working the Pentre and No. 3 Rhondda seams. By 1935 the colliery was running 30 coke ovens, a coal preparation plant and a by-product works, employing 263 on the surface and 570 underground and producing steam, house and manufacturing coals from the bituminous seams. There were 1,006 employed in 1938 and 981 in 1945. Coedely was nationalised in 1947 and placed in the National Coal Board’s South Western Division No. 3 (Rhondda) Area, based at Treorchy, then working the Pentre, Lower Pentre and No. 2 Rhondda seams. Between 1952 and 1960 an underground connection was driven to Cwm Colliery, over five kilometres to the east, as part of a £9 million reconstruction; the merger of the two made the largest colliery in the South Wales coalfield, and through the 1970s the pair produced 515,000 tons of steam coal a year from the Six Feet and Yard seams with 1,580 men between them.

Geology

The South Wales coalfield in the Ely valley. The seams worked included the Four Feet, Pentre, Lower Pentre and No. 2 and No. 3 Rhondda, and later, in the joint working with Cwm, the Six Feet and Yard. The coals were classed as type 301B prime coking coals, used for foundry or blast-furnace coke.

Workings

Two shafts 40 yards apart, both 20 feet in diameter, the No. 1 sunk to 701 yards and the No. 2 to 763. A No. 3 house-coal pit also stood on the site. The colliery carried coke ovens — thirty of them by 1935 — a coal preparation plant and a complete by-product works. From the 1950s an underground roadway connected the workings to Cwm Colliery to the east.

Closure

The colliery closed on 28 November 1986, the same day as Cwm, the pit it had been joined to underground for nearly thirty years.

What remains

No description of the present-day site has been established from the sources read.

No surviving structure has been identified.

Related mines

• Cwm Colliery — Joined underground and closed together: a roadway was driven between the two between 1952 and 1960 as part of a £9 million reconstruction, making the pair the largest colliery in the South Wales coalfield; through the 1970s they produced 515,000 tons a year with 1,580 men between them, and both closed on 28 November 1986.

Nearby mines

• Cymmer Colliery — 2.8 km N
• Lewis Merthyr Colliery — 3.2 km NE
• Naval Colliery — 3.3 km NW
• Great Western Colliery — 4.5 km NE
• Glamorgan Colliery — 5.1 km N

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 Welsh Navigation Steam Coal Co. Ltd began sinking the two shafts at Coedely in 1901, with the first coal produced in 1906. The company was a subsidiary of David Davis and Sons Ltd. ¹
• The No. 1 pit was sunk to 701 yards and the No. 2 to 763 yards. The shafts were 40 yards apart and both were 20 feet in diameter. ¹
• The colliery was equipped with both coke ovens and a complete by-product plant. Its coals were classed as type 301B prime coking coals, for use as foundry or blast-furnace coke. By 1935 it operated 30 coke ovens, a coal preparation plant and a by-product works. ¹
• The workforce numbered 231 in 1908 and 1,450 by 1918. A list of 1923 gives 467 men at No. 1 pit working the Four Feet seam and 1,049 at No. 2 working the Pentre and No. 3 Rhondda seams. There were 1,006 employed in 1938 and 981 in 1945. ¹
• Between 1952 and 1960 an underground connection was constructed linking Coedely with Cwm Colliery, over five kilometres to the east. Through the 1970s the two collieries jointly produced 515,000 tons a year with a workforce of 1,580 men, from the Six Feet and Yard seams. ^1,2
• The colliery closed on 28 November 1986. ²

Photographs & further reading

Sources

1. (secondary) Coedely Colliery — Welsh Coal Mines
2. (secondary) Coedely Colliery — Tonyrefail and District Community Council

Record created: 8 September 2026 · Last researched: 8 September 2026