© Mapbox · © OpenStreetMap contributors · Boundary data © Cadw
Mynydd Rhiw Round Cairns is a prehistoric round cairn situated in Wales on bedrock of mafic igneous rock formed during the Silurian period. The underlying geology, an unnamed intrusion of dark, dense igneous material, would have weathered to produce stone suitable for cairn construction. Round cairns of this type typically date to the Bronze Age and served as burial monuments, often associated with cremation burials and grave goods reflecting the ritual practices of prehistoric Welsh communities.
The monument stands within a landscape shaped by ancient volcanic activity, where Ordovician to Silurian igneous rocks form the foundation of the surrounding terrain. The use of locally available stone from such bedrock was characteristic of Bronze Age monument builders, who selected durable materials that endured across millennia. The specific geological context of Mynydd Rhiw would have determined both the character of the stones available and the visual prominence of the cairn within its moorland setting.
Mynydd Rhiw Round Cairns is protected by Cadw, the Welsh heritage monuments agency, under reference CN102. This designation recognises its archaeological significance as evidence of prehistoric burial practice and settlement patterns in Wales. The monument remains an important record of Bronze Age funerary tradition and the communities who built and used such structures across the Welsh uplands.
Mynydd Rhiw Round Cairns is a scheduled monument protected by Cadw under reference CN102. View the official record →
Mynydd Rhiw Round Cairns is a prehistoric round cairn situated in Wales on bedrock of mafic igneous rock formed during the Silurian period. It is designated a Scheduled Ancient Monument by Cadw under reference CN102.
Mynydd Rhiw Round Cairns 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.
Mynydd Rhiw Round Cairns 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 CN102.
Several scheduled monuments lie within 10 km, including Mynydd Rhiw Stone Axe Factory (0.4 km), Rhiw Burial Chambers (0.9 km), Long House South of Talarfor (1.1 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Mynydd Rhiw Round Cairns'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.
Mynydd Rhiw Round Cairns stands on Unnamed Igneous Intrusion, Ordovician To Silurian, bedrock that formed in the Silurian. The rock here is mafic igneous-rock.