Chris Moon of Britain (R), 51, and Shannon Farar-Griefer, 52, of Hidden Hills, California, compete in the Badwater Ultramarathon in Death Valley National Park, California July 15, 2013. The 135-mile (217 km) race, which bills itself as the world's toughest foot race, goes from Death Valley to Mt. Whitney, California in temperatures which can reach 130 degrees Fahrenheit (55 Celsius). [Photo/Agencies]