A new series of epic 10k runs. No obstacles - this is your chance to take on some of the UK's toughest terrain. Double-knot your trainers and prepare to thigh-burn your way to raising serious money to help beat cancer sooner. Choose your ultimate running challenge from the 10 events taking place at venues across the UK. Three levels of rated toughness. This event features 10k of thigh-burning, stamina-testing inclines, in the toughest of Tough 10 events on the course made famous for hosting the cycling at the 2012 Olympics. Rated 'Toughest'.