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Offa's Dyke: Section S of Bryn yr Owen Farm is an early medieval linear earthwork constructed across the Welsh border landscape. The monument forms part of Offa's Dyke, an eighth-century defensive and administrative frontier that extends over 150 kilometres from the Dee estuary to the Severn estuary. This particular section runs through terrain underlain by the Pennine and South Wales Middle Coal Measures Formation, a geological sequence of mudstone, siltstone, sandstone and ironstone that would have influenced both the construction method and the visibility of the earthwork across the landscape.
The dyke at Bryn yr Owen Farm survives as a substantial linear bank, its form shaped by the local topography and underlying coal measures geology. The combination of sandstone and ironstone layers in the bedrock would have provided some resistance to erosion, allowing the earthwork to retain its profile across difficult terrain. The mudstone and siltstone components of the geology would have furnished material for construction.
The section is protected as a scheduled ancient monument by Cadw under reference DE174, recognising its significance as part of Wales's most prominent early medieval monument. The survival of the dyke here contributes to our understanding of how this frontier was engineered across geologically varied terrain.
Offa's Dyke: Section S of Bryn yr Owen Farm is a scheduled monument protected by Cadw under reference DE174. View the official record →
Offa's Dyke: Section S of Bryn yr Owen Farm is an early medieval linear earthwork constructed across the Welsh border landscape. It is designated a Scheduled Ancient Monument by Cadw under reference DE174.
Offa's Dyke: Section S of Bryn yr Owen Farm dates from the early medieval period, and is classified as a linear earthwork. It is one of over 32,000 scheduled monuments protected across the UK.
Offa's Dyke: Section S of Bryn yr Owen Farm 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 DE174.
Several scheduled monuments lie within 10 km, including Darland Wood Round Barrows (5.5 km), Pont y Cysylltau (6.4 km), Offa's Dyke: Section N & S of Tan-y-Cut (6.7 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Offa's Dyke: Section S of Bryn yr Owen Farm'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.
Offa's Dyke: Section S of Bryn yr Owen Farm stands on Pennine Middle Coal Measures Formation And South Wales Middle Coal Measures Formation (Undifferentiated), bedrock that formed in the Moscovian. The rock here is mudstone, siltstone, sandstone, coal, ironstone and ferricrete.