5 - 6
FATMAP difficulty grade
A high level mountain walk from Storey Arms over Y Gyrn (605 metres) and past the Tommy Jones Memorial up to the two main summits of Corn Du (873 metres) and Pen-y-Fan (886 metres).
From Pen-y-Fan, there are two options to continue with this walk: SHORT OPTION - return to Bwlch Duwynt on the Taff Trail and descend to Pont ar Daf where toilets can be found and there are often refreshments there. LONG OPTION - descent south-easterly to the 665 metre spot height and choose to either ascend Cribyn (795 metres) or follow the Taff Trail south around Cribyn to Bwlch ar y Fan (599 metres).
Follow the Taff Trail on the vehicle width track to the large gully immediately east of the Lower Reservoir Dam.
Do not cross the gully but follow the vehicle track into the reservoir complex and cross the dam.
Beyond the dam climb with the forest boundary fence on the left with a final steep climb up to the Trip, point 642 metres.
From there head northwards along the ridge for approximately 4 kilometres to Bwlch Duwynt and descend to Pont ar Daf from where it is a short walk northwards to Storey Arms.