The race is well established in the Welsh Fell Running calendar .
The race entails running to seven mandatory checkpoints ( including Tor y foel , Corn Ddu , Pen y Fan and Cribyn ) from the dam at Talybont Reservoir .
The race is well established in the Welsh Fell Running calendar and entails running to seven mandatory checkpoints ( including Tor y foel , Corn Ddu , Pen y Fan and Cribyn ) from the dam at Talybont Reservoir .