Pen y Fan same noun "ban", in its plural form "bannau", is found in the Welsh name for the Brecon Beacons: "Bannau Brycheiniog". There is no one standard translation of "Pen y Fan", but 'the mountain's peak' or 'the beacon's summit' are both possible translations. Pen y Fan is formed from various units of the Old Red Sandstone which were laid down during the Devonian period. The lower slopes of the mountain are formed from the sandstones and mudstones of the Senni Formation whilst the upper slopes are formed from those of the Brownstones Formation. The very summit, like that of neighbouring Corn
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