Ultra-runner Karl Meltzer has long dreamed of setting the speed record for crossing America's Appalachian Trail. Now he sets out for his third and final attempt to run the 3,523 km (2,188 miles) in less than 46 days, 8 hours, 6 min.
简介：Ultra-runner Karl Meltzer has long dreamed of setting the speed record for crossing America's Appalachian Trail. Now he sets out for his third and final attempt to run the 3,523 km (2,188 miles) in less than 46 days, 8 hours, 6 min.
