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Remains of Blast Furnaces, Cyfarthfa Ironworks is a post-medieval and modern industrial monument protecting the substantial stonework of iron smelting furnaces. The site lies on bedrock of the Millstone Grit Group, a geological formation of mudstone, siltstone and sandstone deposited during the Namurian period. This foundation of hard sandstone provided stable ground for the heavy structures required in iron production, whilst the surrounding geology of South Wales offered both coal and iron ore essential to ironworking.
The blast furnaces represent the technological development of iron smelting from the post-medieval period into modern times. Such furnaces operated at high temperatures to reduce iron ore, requiring robust brick and stone construction to withstand intense heat and chemical processes. The remains visible today preserve evidence of this industrial past through their architectural form and material composition.
The monument is protected by Cadw, the Welsh heritage agency, under reference GM425. This designation recognises its significance as a relic of Wales's industrial heritage and its contribution to understanding metalworking practices and technological change in Britain. The Cyfarthfa site stands as testimony to the region's importance in iron production during the industrial era.
Remains of Blast Furnaces, Cyfarthfa Ironworks is a scheduled monument protected by Cadw under reference GM425. View the official record →
Remains of Blast Furnaces, Cyfarthfa Ironworks is a post-medieval and modern industrial monument protecting the substantial stonework of iron smelting furnaces. It is designated a Scheduled Ancient Monument by Cadw under reference GM425.
Remains of Blast Furnaces, Cyfarthfa Ironworks dates from the post medieval/modern period, and is classified as a blast furnace. It is one of over 32,000 scheduled monuments protected across the UK.
Remains of Blast Furnaces, Cyfarthfa 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 GM425.
Several scheduled monuments lie within 10 km, including Platform Houses on Coly Uchaf (7 km), Rhos-Gwawr cairn cemetery (7.7 km), Cefn Merthyr Round Cairns (8.1 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Remains of Blast Furnaces, Cyfarthfa 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 Blast Furnaces, Cyfarthfa Ironworks stands on Millstone Grit Group [See Also Migr], bedrock that formed in the Namurian. The rock here is mudstone, siltstone and sandstone.