Pen y Fan (/pɛnəˈvæn/) is the highest peak inSouth Wales, in theBrecon Beacons National Park. At 886 metres (2,907 ft) above sea-level, it is also the highest British peak south ofCadair Idris inSnowdonia. The twin summits of Pen y Fan andCorn Du at 873 metres (2,864 ft) were formerly referred to as Cadair Arthur or 'Arthur's Seat'.
The mountain and surrounding area are owned by theNational Trust whose work parties attempt to combat theerosion caused by the passage of thousands of feet up and down this most popular of South Wales' peaks. The mountain is used by themilitary as part of the selection process of theUK'sSpecial 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 undergoingSpecial Air Service selection.[1]