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Nant Mawr Round Cairn is a prehistoric round cairn located in Wales and protected as an ancient monument by Cadw. The site sits upon Lower Devonian bedrock comprising sandstone and conglomerate laid down in the Early Devonian period, which would have been a stable foundation for the cairn's construction. Round cairns of this type typically date to the Bronze Age and served as burial monuments, with stones gathered from the surrounding landscape piled into a distinctive circular mound.
The monument's position on this geology means that suitable building stone would have been readily available locally, as the fractured Devonian rocks would naturally break into workable pieces. Builders would have sourced material from immediate quarrying rather than transporting it from a distance, making the site's geological setting integral to its construction method and location choice.
Today Nant Mawr Round Cairn remains a significant record of Bronze Age burial practice in Wales. Its preservation by Cadw reflects the importance of round cairns in understanding prehistoric settlement, burial ritual and land use. The monument continues to reveal information about ancient communities through its physical structure and archaeological context within the Welsh landscape.
Nant Mawr Round Cairn is a scheduled monument protected by Cadw under reference BR285. View the official record →
Nant Mawr Round Cairn is a prehistoric round cairn located in Wales and protected as an ancient monument by Cadw. It is designated a Scheduled Ancient Monument by Cadw under reference BR285.
Nant Mawr 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.
Nant Mawr 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 BR285.
Several scheduled monuments lie within 10 km, including Cader Fawr Round Cairn (7.8 km), Cadair Fawr settlement (8 km), Twyn Bryn Glas round cairn (8.6 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Nant Mawr 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.
Nant Mawr Round Cairn stands on Lower Devonian Rocks (Undifferentiated), bedrock that formed in the Early Devonian. The rock here is sandstone and conglomerate, interbedded.