Abercriban Quarries is a Site of Special Scientific Interest in Brecknock, Powys

Powys

Powys is a local-government county and preserved county in Wales.-Geography:Powys covers the historic counties of Montgomeryshire and Radnorshire, most of Brecknockshire , and a small part of Denbighshire — an area of 5,179 km², making it the largest county in Wales by land area.It is...

, Wales

Wales

Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...

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The quarries are located near the village of Pontsticill

Pontsticill

Pontsticill is a village within the county borough of Merthyr Tydfil in South Wales. It lies within the valley of the Taf Fechan on the southern edge of the Brecon Beacons National Park...

, overlookin Pontsticill Reservoir

Pontsticill Reservoir

Pontsticill Reservoir or Taf Fechan Reservoir is a large reservoir on the Taf Fechan lying partly in the county of Powys and partly within the county borough of Merthyr Tydfil in south Wales. It lies within the Brecon Beacons National Park and Fforest Fawr Geopark...

. Abercriban Quarries comprise two small disused quarries. The site is of special interest for the rock exposures of the Grey Grit Formation of the Upper Old Red Sandstone, these exposed rocks span the boundary between the Carboniferous and Devonian periods of geological time, approximately 360 million years ago.