Llanfihangel Moraine
Geology & landscape
Geological Feature: Moraine
Landscape processes: Glacial
Description
Description A large arcuate moraine at Llanfihangel Crucorney marks the terminus of the Late Devensian ice sheet in South Wales. It runs west from Llanfihangel Crucorney for about 1.5 km and rises up to 20 m high above the valley floor. The moraine was probably formed by a southward-moving branch of the Usk glacier and has been responsible for a major diversion of drainage of the Afon Honddu. Over much of South Wales clear evidence for the terminal limits of the Late Devensian ice sheet is lacking, so that the Llanfihangel Crucorney moraine provides important information on this problem. Remarks: Within the Brecon Beacons National Park.