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Offa's Dyke: Section S of Aberderfyn Road is an early medieval linear earthwork in Wales, protected by Cadw under reference DE178. Built in the late eighth century as a frontier marker between the Anglo-Saxon kingdom of Mercia and the Welsh kingdoms, the dyke represents one of Europe's most substantial prehistoric engineering projects. This section follows the undulating terrain above bedrock formed from the Pennine and South Wales Middle Coal Measures, where mudstone, siltstone and sandstone create a landscape of variable elevation that the builders had to negotiate.
The earthwork was constructed by heaping soil and stone into a substantial bank, often accompanied by a ditch to the Welsh side. Along this section of Aberderfyn Road, the underlying coal-bearing strata and iron-rich ferricrete deposits influenced both the availability of construction material and the drainage patterns that affected the dyke's alignment. The monument's preservation and official protection reflect its archaeological and historical importance as evidence of large-scale territorial organisation and labour mobilisation in early medieval Britain.
Offa's Dyke: Section S of Aberderfyn Road is a scheduled monument protected by Cadw under reference DE178. View the official record →
Offa's Dyke: Section S of Aberderfyn Road is an early medieval linear earthwork in Wales, protected by Cadw under reference DE178.
Offa's Dyke: Section S of Aberderfyn Road 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 Aberderfyn Road 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 DE178.
Several scheduled monuments lie within 10 km, including Offa's Dyke: Caeau-Gwynion Section (7.8 km), Offa's Dyke: Chirk Park Section extending NE from the Lake (8.2 km), Offa's Dyke: Chirk Park Section extending 340m NE of Home Farm (8.8 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Offa's Dyke: Section S of Aberderfyn Road'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 Aberderfyn Road 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.