Pen y Fan is the highest peak in southern Britain at 886 metres, sitting in the Brecon…

Pen y Fan is the highest peak in southern Britain at 886 metres, sitting in the Brecon Beacons in south Wales. The Welsh name means roughly “top of the peak” — bannau, the Welsh for “peaks,” gives the Beacons their Welsh name Bannau Brycheiniog. The flat summit is 370-million-year-old Old Red Sandstone, laid down when Wales was south of the equator on a semi-arid floodplain. The twin summits of Pen y Fan and neighbouring Corn Du were once called Cadair Arthur, Arthur’s Chair. There’s a Bronze Age burial cairn on the summit dating to around 2000 BC. The mountain is famously used by the SAS for selection — the “Fan Dance” march has killed soldiers in bad conditions. Over 250,000 people walk it every year. On a clear day you can see across the Severn Estuary into England.​​​​​​​​​​​​​​​​