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Castell-Mawr is a prehistoric hillfort situated in Wales and protected by Cadw under reference ME073. The monument occupies high ground underlain by Ordovician to Silurian mafic igneous bedrock, part of an unnamed intrusion that formed during the Silurian period. This geological foundation of dark, dense volcanic material would have provided a naturally strong base for the structure.
The hillfort exemplifies the Iron Age tradition of hilltop settlement and defence in upland Wales. Its elevated position afforded commanding views of the surrounding landscape, essential for both surveillance and control of territorial boundaries. The solid igneous bedrock offered practical advantages for fortification, providing stable ground for rampart construction and reducing vulnerability to undermining.
As a scheduled monument, Castell-Mawr contributes important evidence to understanding prehistoric settlement patterns and the development of hillfort communities in Wales during the Iron Age. The site's geological setting is integral to its archaeological significance, as the underlying rock formations influenced both its initial selection as a settlement location and the structural characteristics of its defences.
Castell-Mawr is a scheduled monument protected by Cadw under reference ME073. View the official record →
Castell-Mawr is a prehistoric hillfort situated in Wales and protected by Cadw under reference ME073.
Castell-Mawr dates from the prehistoric period, and is classified as a hillfort. It is one of over 32,000 scheduled monuments protected across the UK.
Castell-Mawr 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 ME073.
Several scheduled monuments lie within 10 km, including Tal-y-Gareg Camp (1.3 km), Waen Fach Standing Stone (1.4 km), Llechlwyd Hillfort (1.8 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Castell-Mawr'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.
Castell-Mawr stands on Unnamed Igneous Intrusion, Ordovician To Silurian, bedrock that formed in the Silurian. The rock here is mafic igneous-rock.