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Site 300m SW of Tan-llan is a prehistoric hillfort revealed by aerial photography and now protected by Cadw under reference MG203. The monument occupies high ground in Wales where Wenlock Rocks—a formation of Silurian mudstone, siltstone and sandstone—provide the underlying geology. The earthwork defences are characteristic of Iron Age hillforts, which served as territorial markers, refuges and centres of authority across Britain during the final centuries before the Roman conquest.
The aerial photography that disclosed this site demonstrates how such monuments, invisible or obscure at ground level, become apparent when viewed from above. The crop marks and soil discolourations revealing the fort's plan are a common feature of Silurian geology, where moisture retention in infilled ditches and buried banks contrasts with the surrounding terrain. The topography of this location would have afforded commanding views across the Welsh landscape and strategic control of the surrounding territory.
The fort remains largely unexcavated, preserving archaeological deposits that may yield information about its date of construction, duration of use and the people who occupied it. Such hillforts formed part of a widespread network of defended settlements across Wales, reflecting patterns of settlement and social organisation during the late prehistoric period. The site's preservation under official protection ensures that future archaeological investigation can proceed under controlled conditions.
Site 300m SW of Tan-llan (revealed by aerial photography) is a scheduled monument protected by Cadw under reference MG203. View the official record →
Site 300m SW of Tan-llan is a prehistoric hillfort revealed by aerial photography and now protected by Cadw under reference MG203.
Site 300m SW of Tan-llan (revealed by aerial photography) dates from the prehistoric period, and is classified as a hillfort. It is one of over 32,000 scheduled monuments protected across the UK.
Site 300m SW of Tan-llan (revealed by aerial photography) 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 MG203.
Several scheduled monuments lie within 10 km, including Pentre Camp (2.7 km), Gaer Roman Site (2.8 km), Pen y Coed Hillfort, Cyfronydd (3.3 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Site 300m SW of Tan-llan (revealed by aerial photography)'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.
Site 300m SW of Tan-llan (revealed by aerial photography) stands on Wenlock Rocks (Undifferentiated), bedrock that formed in the Wenlock. The rock here is mudstone, siltstone and sandstone.