Runners head along the walls of Conwy Castle at the start of the race. Photo: No Limits Photography

A brutal multi-day race down the length of Wales is underway, with 367 runners making the start at Conwy Castle.

The field set off at 7am on Monday to tackle the Montane Dragon’s Back Race.

Ahead of them lay 380km of hard running, with 17,400m of ascent including summits in the Carneddau, Glyderau, Tryfan and Wales’s highest mountain Yr Wyddfa-Snowdon, along the grade-one scramble Crib Goch.

The event has been extended this year, with a long traverse over the Brecon Beacons and a finish at Cardiff Castle on Saturday.

At the end of the first day, Welshman Simon Roberts led the race, completing Monday’s course in 7hrs 24mins 14sec, just 13 seconds ahead of second-placed runner Russell Bentley. British athlete Katie Mills leads the women’s race, after arriving at the final checkpoint of the day at Gwastadanas with a time of 9hrs 58mins 6secs, giving her a lead of 51 minutes over Elaine Bisson in second place.

Fancied runners Marcus Scotney, a previous winner of the event, and Kim Collison both retired from the race on the first day.

Runners’ progress can be followed on the Open Tracking website.