© Mapbox · © OpenStreetMap contributors · Boundary data © Cadw
Pen-y-Rhiw Round Cairn is a prehistoric round cairn located in Wales. The monument sits upon bedrock of the South Wales Upper Coal Measures Formation, a Carboniferous sequence of mudstone, siltstone, sandstone, coal, ironstone and ferricrete deposited during the Westphalian period. The underlying geology shaped both the landscape available to prehistoric communities and the stone materials they could access for cairn construction.
Round cairns are characteristic funerary monuments of the Bronze Age, typically built to mark burial sites and serving as focal points for ritual activity. Their construction involved gathering and stacking stone to form a conspicuous mound, visible across the surrounding terrain as a permanent monument to the deceased. The durability of such structures, when built from appropriate stone, ensured their survival into the modern era.
Pen-y-Rhiw Round Cairn is protected by Cadw, the Welsh Historic Monuments service, under the reference MM149. This statutory protection recognises its significance as a prehistoric monument and ensures its preservation for future study and public appreciation. The cairn remains an important archaeological record of Bronze Age burial practice and territorial expression in the Welsh landscape.
Pen-y-Rhiw Round Cairn is a scheduled monument protected by Cadw under reference MM149. View the official record →
Pen-y-Rhiw Round Cairn is a prehistoric round cairn located in Wales. It is designated a Scheduled Ancient Monument by Cadw under reference MM149.
Pen-y-Rhiw Round Cairn dates from the prehistoric period, and is classified as a round cairn. It is one of over 32,000 scheduled monuments protected across the UK.
Pen-y-Rhiw Round Cairn 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 MM149.
Several scheduled monuments lie within 10 km, including Caerphilly Iron Furnace (5 km), Caerphilly Castle (5.1 km), Caerffili Mountain Shaft Mounds (7 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Pen-y-Rhiw Round Cairn'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.
Pen-y-Rhiw Round Cairn stands on South Wales Upper Coal Measures Formation, bedrock that formed in the Westphalian. The rock here is mudstone, siltstone, sandstone, coal, ironstone and ferricrete.