© Mapbox · © OpenStreetMap contributors · Boundary data © Cadw
Garth Hill Platform House is a medieval platform house situated in Wales on bedrock of the South Wales Upper Coal Measures Formation. The underlying geology comprises mudstone, siltstone and sandstone interspersed with coal seams, ironstone and ferricrete deposits dating to the Westphalian period. This carboniferous foundation would have presented particular constraints and opportunities for medieval builders, who levelled the uneven terrain to create the substantial stone platform upon which the dwelling was constructed.
Platform houses represent a distinctive medieval building tradition, particularly common in upland and marginal areas where naturally sloping ground required deliberate terracing. The platform at Garth Hill was engineered to provide a level building plot, a practical solution that allowed settlement in challenging topography. The surrounding landscape of the South Wales coalfield, with its varied geology and often steep terrain, made such platforms necessary for permanent occupation.
The monument is protected by Cadw, the Welsh heritage monuments authority, under the reference number GM552. This designation recognises the archaeological and historical significance of the site as evidence of medieval settlement patterns and building practices adapted to the particular demands of the Welsh landscape. The platform house survives as a tangible record of how medieval communities engineered their environment to establish stable domestic spaces.
Garth Hill Platform House is a scheduled monument protected by Cadw under reference GM552. View the official record →
Garth Hill Platform House is a medieval platform house situated in Wales on bedrock of the South Wales Upper Coal Measures Formation. It is designated a Scheduled Ancient Monument by Cadw under reference GM552.
Garth Hill Platform House dates from the medieval period, and is classified as a platform house. It is one of over 32,000 scheduled monuments protected across the UK.
Garth Hill Platform House 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 GM552.
Several scheduled monuments lie within 10 km, including Cefn Cross Standing Stone (7.4 km), Pen-y-Castell Camp (7.9 km), Remains of Iron Furnace Near Angleton (8.6 km).
This page is just one thread. A full Aubrey report pulls together 13 strands of Garth Hill Platform House'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.
Garth Hill Platform House stands on South Wales Upper Coal Measures Formation, bedrock that formed in the Westphalian. The rock here is mudstone, siltstone, sandstone, coal, ironstone and ferricrete.