© Mapbox · © OpenStreetMap contributors · Boundary data © Cadw
Twyn-y-Gaer is a prehistoric enclosure located in Wales, protected by Cadw under reference BR034. The monument sits upon bedrock comprising Pridoli rocks of undifferentiated character, a geological formation of mudstone, siltstone and sandstone laid down during the Pridoli epoch. These fine-grained sediments provide a stable foundation typical of upland Welsh terrain.
The enclosure represents a form of settlement or territorial marker common to prehistoric Britain, when communities established defended or demarcated spaces for habitation, livestock management or ceremonial purposes. The specific topography and geology of Twyn-y-Gaer would have influenced its original function and construction methods, with the underlying Pridoli bedrock shaping both the drainage and the availability of stone for rampart building.
As a scheduled monument under Cadw's stewardship, Twyn-y-Gaer remains an important record of prehistoric land use and social organisation in Wales. The site contributes to understanding how early communities adapted to and modified the Welsh landscape, responding to local geology and topography in their choice of defensive or administrative locations.
Twyn-y-Gaer is a scheduled monument protected by Cadw under reference BR034. View the official record →
Twyn-y-Gaer is a prehistoric enclosure located in Wales, protected by Cadw under reference BR034.
Twyn-y-Gaer dates from the prehistoric period, and is classified as a enclosure. It is one of over 32,000 scheduled monuments protected across the UK.
Twyn-y-Gaer 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 BR034.
Several scheduled monuments lie within 10 km, including Town Wall at Watton Mount (6.8 km), Slwch Camp (6.8 km), Town Wall and Gatehouse at Captain's Walk (6.9 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Twyn-y-Gaer'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.
Twyn-y-Gaer stands on Pridoli Rocks (Undifferentiated), bedrock that formed in the Pridoli. The rock here is mudstone, siltstone and sandstone.