The Brecon Beacons range, in its truest sense, is a series of mountains to the south
of Brecon. There are six main peaks: from west to east these are: Corn Du (873 m
or 2864 feet), Pen y Fan, the highest peak (886 m or 2907 feet), Cribyn (795 m or
2608 feet), Fan y Big (719 m or 2359 feet), Bwlch y Ddwyallt (754 m or 2474 ft) and
Waun Rydd (769 m or 2523 ft). These summits form a long ridge, and the sections joining
the first four form a horseshoe shape around the head of the Taf Fechan river, which
flows away to the south-east. To the northeast of the ridge, interspersed with long
parallel spurs, are four round-headed valleys or cwms; from west to east these are
Cwm Sere, Cwm Cynwyn, Cwn Oergwm and Cwm Cwareli.
The Brecon Beacons are said to be named after the ancient practice of lighting signal
fires (beacons) on mountains to warn of attacks by invaders, or more recently to
commemorate public and national events such as coronations or the Millennium.
The round of the Taf Fechan skyline forms a popular ridge walk commonly known as
the 'Beacons Horseshoe'. Many other fine walks exist in this part of the National