Alex Honnold scaled the 3,000-foot face of El Capitan without ropes on Saturday. Getty Images

Renowned rock climber Alex Honnold has achieved what fellow climber Tommy Caldwell has called "The 'moon-landing' of free-soloing.

Honnold, 31, scaled Yosemite National Park's famous 3,000-foot peak El Capitan in 3 hours, 56 minutes, with National Geographic capturing parts of the climb. It is already considered by many to be the most dangerous free-solo (scaling a peak without ropes or safety gear) climb to ever be completed.

Here's National Geographic's exclusive photo of Honnold after completing his climb.

Honnold has been training for the climb for more than a year and planning it for even longer, using various locations in the United States, China, Europe and Morocco. Very few close friends of Honnold knew of the climb, and they all were forced to remain silent about Saturday's attempt.

Honnold says that it's his ability to control his fear that makes him a successful free solo climber. He has long been one of the premier faces of rock climbing, and this climb cements his legacy as one of the most successful climbers in history.

"With free-soloing, obviously I know that I'm in danger," Honnold told National Geographic. "But feeling fearful while I'm up there is not helping me in any way. It's only hindering my performance, so I just leave it aside and let it be."

The most daunting part of the trek is a stretch called "Freerider," which Honnold referred to as being like "walking up glass." It's two pitches of sheer rock that doesn't offer any hand-holds due to erosion. Honnold prepared for this by hiking up it with ropes a few days before the climb, marking holding spots with chalk.

During the final stretch, observers said that Honnold was nearly at a running pace.

The end of Honnold's climb was filmed and captured by National Geographic. Footage of the climb will be released in the near future.