If it weren’t so exposed, this single track that Kilian Bron rides in the Dolomites looks pretty fun. But any sort of screw up and you’d be picking rocks out of your skin from a 2,000-foot slide. If you could still lift up your arms. “It was as stressful as it was exciting,” he said on his YouTube page. But Kilian pretty much sticks it. We wouldn’t have liked to see the results if he hadn’t.