Ynysfach Colliery

Overview

A 19th-century Merthyr Tydfil mine beside the Ynysfach Ironworks, built in 1801 as an extension of Cyfarthfa and long since fallen into infamous ruin.

History

Ynysfach Colliery was a 19th-century mine situated near the Ynysfach Ironworks, on the right bank of the River Taff just west of Merthyr Tydfil town centre. The ironworks it fed was built in 1801 for Richard Crawshay as an extension of the nearby Cyfarthfa works, and the two together held eleven furnaces in blast by 1850, all by then the sole property of William Crawshay. A tramroad ran from Cyfarthfa to the Ynysfach Works, passing close to the Dynevor Arms on the way.

Two blast furnaces were built there to plans by Watkin George, Cyfarthfa's engineer, and two more were added with a new engine house in 1836. As iron gave way to steel in the second half of the 19th century, the Ynysfach works closed, in 1874. Its coke ovens went on to a very different local afterlife, becoming a well-known haunt for the homeless and destitute of Merthyr — remembered locally as the scene of an epic three-hour bare-knuckle bout between Redmond Coleman and Tommy Lyons, and, after a 1908 murder nearby, said to be haunted by the ghost of the victim, Mary Ann Rees.

Recorded claims

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

• A 19th-century mine situated near the Ynysfach Ironworks. ¹
• The Ynysfach Ironworks was built in 1801 for Richard Crawshay as an extension of the neighbouring Cyfarthfa works; together the two held eleven furnaces in blast by 1850, all by then the property of William Crawshay, with a tramroad running from Cyfarthfa to Ynysfach. ²
• As iron gave way to steel, the Ynysfach works closed and its coke ovens became a well-known local haunt for the homeless and destitute of Merthyr, with associated local folklore including a long bare-knuckle boxing match and, after a 1908 murder nearby, a reputed ghost. ²
• The Ynysfach Ironworks were founded in 1801 with two blast furnaces; two more and an engine house were built in 1836, and the works closed in 1874. ³

Photographs & further reading

Sources

1. (secondary) Small Collieries around Merthyr Tydfil — Northern Mine Research Society
2. (secondary) Ynysfach Works — The Melting Pot (Merthyr Tydfil's History and Culture)
3. (secondary) Ynysfach Engine House, Cyfarthfa, Merthyr Tydfil (listed building description) — British Listed Buildings (Cadw listing text)

Record created: 15 September 2026 · Last researched: 16 October 2026