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Canal Aqueduct over the River Twrch, Ystalyfera is a post-medieval aqueduct carrying water across the River Twrch valley in the industrial landscape of South Wales. The structure stands above bedrock formed from the Pennine and South Wales Middle Coal Measures, a geological succession of mudstone, siltstone, sandstone, coal and ironstone that was laid down in the Moscovian period. This coal-rich landscape shaped the region's industrial heritage, and the aqueduct reflects the infrastructure demands of the era's works and settlements.
The aqueduct represents the engineering solutions developed to transport water across the challenging topography of the South Wales valleys. Built to bridge the Twrch's gorge, it exemplifies the canal engineering of its period, adapted to local geology and valley formation. The structure remains a physical record of the practical ingenuity required to support industrial communities in upland terrain where water management was critical to manufacturing processes and domestic supply.
The monument is protected by Cadw, the Welsh Historic Monuments service, under reference GM396, recognising its historical significance as part of South Wales' industrial heritage infrastructure.
Canal Aqueduct over the River Twrch, Ystalyfera is a scheduled monument protected by Cadw under reference GM396. View the official record →
Canal Aqueduct over the River Twrch, Ystalyfera is a post-medieval aqueduct carrying water across the River Twrch valley in the industrial landscape of South Wales. It is designated a Scheduled Ancient Monument by Cadw under reference GM396.
Canal Aqueduct over the River Twrch, Ystalyfera dates from the post medieval/modern period, and is classified as a aqueduct. It is one of over 32,000 scheduled monuments protected across the UK.
Canal Aqueduct over the River Twrch, Ystalyfera 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 GM396.
Several scheduled monuments lie within 10 km, including Cairn on Mynydd-March-Hywel (5.5 km), Two Platform Houses 1600m SE of Blaen-Nant Farm (6.8 km), Standing Stones 300m W of Cefncelfi (6.9 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Canal Aqueduct over the River Twrch, Ystalyfera'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.
Canal Aqueduct over the River Twrch, Ystalyfera 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.