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Remains of Tondu Ironworks is a post-medieval and modern industrial site in Wales, protected as a scheduled monument by Cadw. The ironworks exploited the rich mineral resources of the South Wales coalfield, which lies directly beneath the site within the Pennine Middle Coal Measures Formation. This geological sequence, formed during the Moscovian period, contains the mudstones, siltstones and sandstones interspersed with coal seams and ironstone layers that made the South Wales valleys centres of iron production from the eighteenth century onwards.
The site preserves structural and archaeological remains from the ironworks' operational period, recording the industrial heritage of a region that became one of Britain's most significant iron-producing areas. The underlying geology—particularly the accessible ironstone and coal deposits—made Tondu an economically viable location for smelting and metalworking operations.
Today, the remains offer evidence of Wales's industrial past and the relationship between geological resources and industrial development. The site is managed as a heritage asset of regional importance, allowing visitors and researchers to understand the technological and economic significance of iron production in the South Wales coalfield.
Remains of Tondu Ironworks is a scheduled monument protected by Cadw under reference GM433. View the official record →
Remains of Tondu Ironworks is a post-medieval and modern industrial site in Wales, protected as a scheduled monument by Cadw. It is designated a Scheduled Ancient Monument by Cadw under reference GM433.
Remains of Tondu Ironworks dates from the post medieval/modern period, and is classified as a ironworks. It is one of over 32,000 scheduled monuments protected across the UK.
Remains of Tondu Ironworks is a Scheduled Ancient Monument, legally protected by Cadw — the body responsible for designating and safeguarding heritage sites in Wales. The official designation reference is GM433.
Several scheduled monuments lie within 10 km, including Merthyr Mawr Churchyard Cross (7 km), Vervil Dyke (7 km), Candleston Castle (7.5 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Remains of Tondu Ironworks's history, each drawn from the record and mapped to the exact spot:
Every location is different. Not every section appears for every place, only what the historical record actually holds turns up in a report.
Remains of Tondu Ironworks stands on Pennine Middle Coal Measures Formation And South Wales Middle Coal Measures Formation (Undifferentiated), bedrock that formed in the Moscovian. The rock here is mudstone, siltstone, sandstone, coal, ironstone and ferricrete.