Pen y Fan Pen y Fan Pen y Fan () is the highest peak in south Wales, situated in the Brecon Beacons National Park. At above sea-level, it is also the highest British peak south of Cadair Idris in Snowdonia. The twin summits of Pen y Fan and Corn Du at 873 m (2,864 ft) were formerly referred to as Cadair Arthur or 'Arthur's Seat'. The mountain and surrounding area are owned by the National Trust whose work parties attempt to combat the erosion caused by the passage of thousands of feet up and down this most popular of South Wales' peaks. The
Pen y Fan mountain is used by the military as part of the selection process of the UK's Special Forces personnel. Three soldiers who died after collapsing in the field in July 2013 were believed to have been climbing the mountain (see "Fan Dance") while undergoing Special Air Service selection. The peak is a major objective in the Beacons Way, a long distance footpath which passes from east to west across the massif, and is open to all walkers. There is well made, evenly graded footpath from the Storey Arms on the A470, which is 1500 feet below, allowing for safe access during