A decade or so ago, the Dawn Wall wasn't on the radar of even the best climbers. The holds are so small that the walls appear to be blank, and must be climbed in chilly temperatures so that perspiration doesn't interfere with holding on to the razer-thin rock.

"Most people would be intimidated just standing at the base," Hill said. "There are really only a few people who push things."

Namely, Caldwell, who is a connoisseur of challenging climbing, Chin said: "So if anyone is going to pick the hardest possible thing on El Cap, it's Tommy."

Of course, each generation has made such vast improvements in the sport that perhaps, Chin said, "three generations from now, maybe climbers will be doing laps on that route. Who knows?"