Seven Sisters Colliery

Also known as	Blaendulais Colliery
Location	Seven Sisters (Blaendulais), Dulais Valley, Neath Port Talbot — 51.7684, -3.7238 (approximate)
Commodity	Coal
Type	Coal
Worked	1872–1963
Maximum depth	Both shafts sunk to the Nine Feet anthracite seam, 200 yards from the surface.
Operators	Evans and Bevan (1872–1947), National Coal Board (1947–1963)

Overview

An anthracite colliery in the Dulais Valley whose first sod was cut with a silver spade in March 1872, and which gave its name to the village that grew around it. Its two shafts reached the Nine Feet anthracite seam at 200 yards. It employed over 750 men at its peak in 1945 and closed in May 1963, its workforce transferring to Blaenant.

History

The first sod was cut on Monday 11 March 1872, with a silver spade, at Bryn Dulais farm, by Isabella Bevan of the Evans and Bevan mine-owning partnership; six sisters were also present at the ceremony, and the colliery and then the village took their name from them. Two shafts were sunk — an elliptical upcast of 12 feet by 9, and a downcast of 14 feet — both to the Nine Feet anthracite seam, found 200 yards from the surface. The downcast wound the coal and the upcast wound only men. A shaft accident killed three when a guide rope broke and tipped men out of the cage: Thomas Thomas, thirty-one, his brother John Thomas, twenty, and William Lewis, fifteen. The Inspector of Mines' list for 1896 records 296 men at the colliery. On 10 November 1907 an underground explosion caused by a defective safety lamp killed five men. The manager prosecuted the fireman for having an unlocked lamp in the mine and the surface lampman for letting a defective lamp be given out, and convictions were obtained in both cases. By 1923 the colliery employed 607 men working the Furnace Four Feet, Brass and Nine Feet Big Vein seams, and at its peak in 1945 more than 750. Geological problems and changing economics told against it through the 1950s, and in May 1963 the colliery closed and the pit was filled in. The men were transferred to the nearby Blaenant Colliery.

Geology

The colliery worked the anthracite of the western end of the South Wales Coalfield, where the coal has been carried to the highest rank — the Nine Feet seam here being an anthracite rather than the steam coal the same seam gives further east. Anthracite districts are prone to sudden outbursts of gas, which is what the 1907 explosion was attributed to, and it was geological difficulty as much as economics that closed the pit in 1963.

Workings

Two shafts: an elliptical upcast of 12 feet by 9 feet, used for winding men only, and a downcast of 14 feet in diameter, used for winding coal. Both were sunk to the Nine Feet anthracite seam at 200 yards. By 1923 the colliery was also working the Furnace Four Feet and Brass seams alongside the Nine Feet Big Vein.

Closure

Geological problems and changing economic conditions told against the colliery through the 1950s. It closed in May 1963 and the pit was filled in; the men were transferred to Blaenant Colliery.

What remains

The pit was filled in on closure. The village survives, including Brick Row — the single-storey dwellings first built for the colliers, still standing.

No colliery structures; Brick Row, the first miners' housing, survives in the village.

Related mines

Blaenant Colliery — When Seven Sisters closed in May 1963 and its pit was filled in, the men employed there were transferred to the nearby Blaenant Colliery in the same valley.

Nearby mines

Blaenant Colliery — 3.0 km SE
Gleision Colliery — 6.1 km SW
Cefn Coed Colliery — 6.3 km SW
Aberpergwm Colliery — 6.6 km E
Tarenni Colliery — 6.6 km SW

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

Disasters & major incidents

Seven Sisters Colliery Explosion, 1907
10 November 1907 · Explosion · 5 fatalities
An underground explosion at Seven Sisters Colliery on 10 November 1907 killed five men. It was attributed to a defective safety lamp, and the manager afterwards prosecuted both the fireman who had an unlocked lamp underground and the surface lampman who had let a defective one be given out. Both were convicted.

Recorded claims

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

The first sod was cut on Monday 11 March 1872 by Isabella Bevan, with a silver spade, at Bryn Dulais farm; the colliery and the village took their name from the sisters present. (medium) ^1,2
The colliery had an elliptical upcast shaft of 12 feet by 9 feet and a downcast of 14 feet in diameter, both sunk to the Nine Feet anthracite seam 200 yards from the surface; the downcast wound coal and the upcast only men. (medium) ¹
The Inspector of Mines' list for 1896 records 296 men; by 1923 there were 607 working the Furnace Four Feet, Brass and Nine Feet Big Vein seams, and at its peak in 1945 the colliery employed over 750. (medium) ^1,2
Geological problems and changing economic conditions closed the colliery in May 1963; the pit was filled in and the men transferred to the nearby Blaenant Colliery. (medium) ²
A guide rope broke and tipped men out of the cage, killing Thomas Thomas, 31, his brother John Thomas, 20, and William Lewis, 15. Welsh Coal Mines dates this to 26 August 1979, which cannot be right for a colliery that closed in 1963; 1879 is the likely date. (disputed) ¹

Photographs & further reading

Welsh Coal Mines: Seven Sisters Colliery, Dulais Valley (reference)

The cutting of the first sod and the naming of the colliery, its shaft dimensions and the anthracite seam they reached, and accounts of the shaft accident and the 1907 explosion with the names of the dead.

View source

Sources

(secondary) Seven Sisters Colliery, Dulais Valley — Welsh Coal Mines
(secondary) Seven Sisters, Neath Port Talbot — Wikipedia

Record created: 3 September 2026 · Last researched: 3 September 2026