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Pen y Gaer is a Roman fort situated on Lower Devonian bedrock in Wales. The underlying geology comprises mudstone, siltstone and sandstone laid down during the Early Devonian period, providing a solid foundation for the fort's construction. The fort occupies a strategically significant position within the Welsh landscape, reflecting Roman military planning in this frontier region.
The fort is protected as a scheduled monument under Cadw reference BR174, ensuring its preservation for future study and public access. Its layout and dimensions are consistent with other auxiliary forts of the Roman occupation, designed to accommodate a garrison force and support administrative functions across the territory. The fort's placement demonstrates Roman understanding of local topography and defensibility.
Today Pen y Gaer survives as an archaeological monument, its earthwork remains visible across the landscape. The site retains potential for further archaeological investigation, with the underlying geology having preserved organic and inorganic materials from the Roman period. As a protected heritage site, it contributes to our understanding of Roman military strategy and occupation in Wales during the first and second centuries AD.
Roman Fort at Pen y Gaer is a scheduled monument protected by Cadw under reference BR174. View the official record →
Pen y Gaer is a Roman fort situated on Lower Devonian bedrock in Wales. It is designated a Scheduled Ancient Monument by Cadw under reference BR174.
Roman Fort at Pen y Gaer dates from the roman period, and is classified as a fort. It is one of over 32,000 scheduled monuments protected across the UK.
Roman Fort at Pen 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 BR174.
Several scheduled monuments lie within 10 km, including Mynydd Llangattock round cairn (7 km), Mynydd Pen-cyrn round cairn (7.9 km), Garn Fawr round cairn (8.1 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Roman Fort at Pen 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.
Roman Fort at Pen y Gaer stands on Lower Devonian Rocks (Undifferentiated), bedrock that formed in the Early Devonian. The rock here is mudstone, siltstone and sandstone.