Garn Goch

Y Garn Goch is a hill in the Brecon Beacons National Park (Parc Cenedlaethol Bannau Brycheiniog) in the east of Carmarthenshire, Wales. The name means the 'red cairn'. It lies near the village of Bethlehem, three miles southwest of Llangadog and four miles east of Llandeilo on the southern side of the broad Towy Valley. It is also commonly known as either Garn Goch or Carn Goch. Current landowners are the Brecon Beacons National Park Authority.

Y Garn Goch is formed from the coarse sandstones of the Ffairfach Grit Formation of the early Ordovician period. A northeast-southwest oriented anticline (the Garn Goch Anticline) which runs through Y Garn Goch can be seen to fold these rocks. The sandstones and mudstones of the Abergwili and Llandeilo Flags Formations form the lower slopes of the hill to north and south. A fault runs northeast-southwest through the col between the two tops and is considered a part of the Welsh Borderland Fault System. The lower ground is mantled by glacial till, a legacy of the last ice age when the valley was filled by the Towy Valley glacier. The hill lies within Fforest Fawr Geopark designated in respect of the outstanding geological heritage of the region.

Y Garn Goch is notable for the two impressive Iron Age hillforts of Y Gaer Fawr, (English: the big fort) and Y Gaer Fach, (English: the little fort), together the largest in southern Wales. There is evidence on site of occupation possibly from Neolithic times through to the Mediaeval period though not necessarily of a continuous nature. Bronze Age burial mounds are a significant feature of the site.

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