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Offa's Dyke Section South of River Gwenfro is a early medieval linear earthwork constructed across the Welsh landscape during the 8th century. The dyke represents one of the most substantial monuments of the Anglo-Saxon period in Britain, built as a frontier demarcation between the Kingdom of Mercia and the Welsh kingdoms to the west. This particular section lies south of the River Gwenfro and survives as an earthen bank, a testament to the scale of labour mobilised for its construction across challenging terrain.
The monument sits upon bedrock of the Pennine and South Wales Middle Coal Measures Formation, comprising mudstone, siltstone and sandstone interspersed with coal seams and ironstone. These geological layers, deposited during the Moscovian period of the Carboniferous, would have presented significant difficulties for the original builders, yet the dyke was engineered to follow the contours of the land, adapting to the local topography. The ferricrete deposits within the underlying strata would have affected soil conditions and water drainage across the site.
The section is protected as a scheduled ancient monument by Cadw, the Welsh heritage body, under reference DE183. This protection recognises the dyke's importance as a physical manifestation of early medieval territorial control and the engineering capabilities of Anglo-Saxon Mercia.
Offa's Dyke Section South of River Gwenfro is a scheduled monument protected by Cadw under reference DE183. View the official record →
Offa's Dyke Section South of River Gwenfro is a early medieval linear earthwork constructed across the Welsh landscape during the 8th century. It is designated a Scheduled Ancient Monument by Cadw under reference DE183.
Offa's Dyke Section South of River Gwenfro 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 South of River Gwenfro 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 DE183.
Several scheduled monuments lie within 10 km, including Gardden Camp (6.9 km), Offa's Dyke: Y Gardden Camp Section (7.1 km), Wat's Dyke: Section extending from Black Brook Bridge to Pentre-Clawdd (7.2 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Offa's Dyke Section South of River Gwenfro'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 South of River Gwenfro 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.