In 1992 a 300km mountain race was run along the upland spine of Wales. Over five days some of the world's leading mountain runners took on the wild terrain to race the length of the country from north to south. Very few made it to the finishing line of the Dragon's Back Race, and since then many have considered it one of the toughest mountain running events ever staged.

Helene Whitaker and Martin Stone who raced together eventually won the 1992 race. Helene astounded many by beating some of the world's top male runners.

Twenty years later 84 runners from 15 countries lined up at Conwy Castle looking to repeat the feat, amid fierce competiton. Helene Whitaker returned to race again alongside three other veterans of the original race.

The 2012 route was even harder than the original Dragon's Back Race, and included all the Welsh 3000ft mountains on the first day, a number of additional summits on the other days, and less road running throughout. See the race report on UKH.

Here's a trailer from the film of last year's race. The movie's available here from the 1st April, and promises beautiful scenery and plenty of pain: