Not content with competing in one of the many challenging traditional triathlons, Charlie Wittmack plans to complete what could be the toughest endurance event in the world. The 33-year-old lawyer from Iowa will start his ultra-tri in the UK with a 442 km swim down the Thames and then cross the English Channel to France. From there he will ride his bike 14, 484 km across Europe and Asia to reach the Bay of Bengal. Wittmack will then run 1,528 km from sea level up to the Nepalese Himalaya and hopefully finish by summiting Everest. More details here.