Gaer, Black Mountains

Gaer is a hill in the Black Mountains of the Brecon Beacons National Park in Monmouthshire, Wales [1]. It lies at the southern end of a long ridge between the valley of the Grwyne Fawr and the Vale of Ewyas, approximately one mile north of Bryn Arw and three miles northeast of Sugarloaf [1]. Its summit at 427 metres above sea level sits within an Iron Age hillfort known as Twyn y Gaer [1].