Ynysawdre Colliery

Overview

A two-shaft colliery at Tondu, also called Adare Colliery, sunk by 1875 to the Cribbwr Fawr seam at 623 feet, with fifty coke ovens beside it from about 1890; it closed in 1898.

History

Ynysawdre, also spelt Ynisawdre and known as Adare Colliery, lay at Tondu on the southern edge of the coalfield, between Park Slip Colliery to the west and Bryncethin to the east. It had two shafts, a winding shaft and a return, sunk to the Cribbwr Fawr seam, which they met at 623 feet 4 inches and which ran about five feet thick; a sinker died in a fall down the shaft in 1874, and the pit is on the Ordnance Survey of 1875. The Ynisawdre Coal, Coke and Brick Company owned it in 1878, with R. Bates as manager, and the Five Quarter seam was abandoned in July 1881.

About 1890 a battery of fifty coke ovens was built alongside, fed with small coal from the Ogmore and Garw valleys and from the soft Boddwr Fawr vein near the surface. In 1896, as Adare Colliery of the Adare Coal and Coke Company of Swansea, it employed 158 men, 57 of them at the surface, producing house and coking coal. The colliery closed in 1898 and the coke ovens about 1900. Cory Brothers owned the site.

In 1915 new slants were driven from the surface beside the old pit, but they broke into old workings, were flooded by percolating water and never found a workable seam; they were abandoned in 1918 according to Welsh Coal Mines, in October 1921 according to NMRS and the abandonment plan.

Geology

South Wales coalfield, near the southern outcrop: the Cribbwr Fawr seam, about five feet, with a shale roof and hard fireclay floor; the Boddwr Fawr, about five feet here, soft and yielding small coal for coking; and the Five Quarter. The coals were high-volatile, used for gas-making and coking.

Workings

Two shafts, winding and return, to the Cribbwr Fawr; a battery of fifty coke ovens from about 1890; trial slants of 1915.

Closure

Closed in 1898; the coke ovens about 1900. Trial slants of 1915 were abandoned in 1918 or 1921 without finding workable coal.

What remains

Unknown.

Redevelopment

Unknown.

What's uncertain

Points where sources disagree or the record could not be settled; both accounts are kept. All open questions in the archive.

• Slants driven in 1915 failed to find workable coal and were abandoned in 1918. (disputed) ²
• Surface drivages opened in 1915 were abandoned in October 1921 without finding a workable seam. (disputed) ^1,4

Recorded claims

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

• Two shafts were sunk to the Cribbwr Fawr seam, met at 623 feet 4 inches. ^1,2
• Owned in 1878 by the Ynisawdre Coal, Coke and Brick Company Ltd. ¹
• A battery of fifty coke ovens was built alongside about 1890 and closed about 1900. ²
• As Adare Colliery it employed 101 men underground and 57 at the surface in 1896. ¹
• Closed in 1898. ^1,2
• The Cribbwr and Five Quarter seams were abandoned in 1881. ³
• Slants driven in 1915 failed to find workable coal and were abandoned in 1918. (disputed) ²
• Surface drivages opened in 1915 were abandoned in October 1921 without finding a workable seam. (disputed) ^1,4

Photographs & further reading

Sources

1. (secondary) Ynisawdre Colliery; Adare Colliery — Northern Mine Research Society
2. (secondary) Ynysawdre Colliery, Tondu — Welsh Coal Mines
3. (primary) BGS mine plans: Ynysawdre, Cribbwr and Five Quarter, 1881 — British Geological Survey / Mining Remediation Authority
4. (primary) BGS mine plans: Ynysawdre, coal not proved, 1921 — British Geological Survey / Mining Remediation Authority

Record created: 7 October 2026 · Last researched: 7 October 2026