© Mapbox · © OpenStreetMap contributors · Boundary data © Cadw
Leat & Dam at Llanmihangel Mill is a post-medieval and modern watercourse and impoundment structure that supplied water to the historic mill. The leat channels water from its source across the local landscape through carefully engineered earthworks, whilst the dam itself creates a reliable head of water necessary for powering the mill's machinery. The structure reflects centuries of Welsh industrial practice, adapting the natural hydrology of the site to support grain milling operations.
The monument sits upon Triassic bedrock comprising interbedded sandstone and conglomerate, which has weathered to create the undulating terrain typical of this geological region. This substrate influenced both the route of the leat and the siting of the dam, as the underlying geology determined water flow patterns and the stability of the earthworks. The local landscape's natural water resources made this location favourable for industrial use.
The leat and dam at Llanmihangel Mill represent the considerable civil engineering knowledge required to sustain rural industrial production. Such structures required regular maintenance and repair to remain effective, and evidence of modifications and rebuilding often reflects changes in milling techniques or the mill's economic fortunes. The monument is protected by Cadw under reference GM449.
Leat & Dam at Llanmihangel Mill is a scheduled monument protected by Cadw under reference GM449. View the official record →
Leat & Dam at Llanmihangel Mill is a post-medieval and modern watercourse and impoundment structure that supplied water to the historic mill. It is designated a Scheduled Ancient Monument by Cadw under reference GM449.
Leat & Dam at Llanmihangel Mill dates from the post medieval/modern period, and is classified as a leat. It is one of over 32,000 scheduled monuments protected across the UK.
Leat & Dam at Llanmihangel Mill 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 GM449.
Several scheduled monuments lie within 10 km, including Mynydd Herbert Round Barrow (4 km), Nottage Court Inscribed Stone (4.3 km), Dan-y-Graig Roman villa (4.8 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Leat & Dam at Llanmihangel Mill'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.
Leat & Dam at Llanmihangel Mill stands on Triassic Rocks (Undifferentiated), bedrock that formed in the Triassic. The rock here is sandstone and conglomerate, interbedded.