© Mapbox · © OpenStreetMap contributors · Boundary data © Cadw
Southernmost Cairn on Pen Plynlimon-Fawr is a prehistoric round cairn situated in the uplands of Wales. The monument occupies high moorland terrain, with bedrock of Ashgill rocks comprising mudstone, siltstone and sandstone formations of Ordovician age. The exposed geology of this period is characteristic of the region's ancient landscape, which would have been familiar to the Bronze Age communities who constructed the cairn. The site enjoys statutory protection as a Scheduled Ancient Monument under Cadw reference CD150.
Round cairns of this type typically date to the Bronze Age, representing burial monuments or ritual sites. Their construction involved gathering local stone to form substantial mounds, often marking significant locations within the prehistoric landscape. The exposed, elevated setting of this cairn would have made it a prominent feature in the surrounding terrain, visible across considerable distances and likely forming part of a broader pattern of ceremonial monuments across the upland zone.
Today the cairn remains as a tangible reminder of Bronze Age settlement and ritual practice in the Welsh uplands. Its preservation allows for the study of prehistoric social organisation and the use of high moorland environments. The monument's survival in this relatively remote location reflects both the durability of stone construction and the protective measures now in place to safeguard Wales's archaeological heritage.
Southernmost Cairn on Pen Plynlimon-Fawr is a scheduled monument protected by Cadw under reference CD150. View the official record →
Southernmost Cairn on Pen Plynlimon-Fawr is a prehistoric round cairn situated in the uplands of Wales. It is designated a Scheduled Ancient Monument by Cadw under reference CD150.
Southernmost Cairn on Pen Plynlimon-Fawr 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.
Southernmost Cairn on Pen Plynlimon-Fawr 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 CD150.
Several scheduled monuments lie within 10 km, including Nant yr Helygen Deserted Rural Settlement (6.4 km), Esgair Naint Deserted Rural Settlement (6.8 km), Hen Bont, Pont-Erwyd (7.2 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Southernmost Cairn on Pen Plynlimon-Fawr'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.
Southernmost Cairn on Pen Plynlimon-Fawr stands on Ashgill Rocks (Undifferentiated), bedrock that formed in the Ashgill. The rock here is mudstone, siltstone and sandstone.