Mount Marathon

In the sixth episode of Salomon Running’s fifth season, Rickey Gates, Kilian Jornet and Emelie Forsberg head to The Last Frontier for the Mount Marathon Race, one of the toughest mountain races in the world. Although it’s only five kilometers in length (a mile and a half up, a mile and a half down), the trail—marked by cliffs, scree fields, and waterfalls—typically holds snow, mud, ice, and rocks. First raced in 1915, there’s nothing else quite like it.