You likely heard this week about 31-year-old rock climber Alex Honnold's astonishing free-soloing feat up the 3,000-foot sheer wall of Yosemite's El Capitan. We know the whole thing was filmed, and now National Geographic brings us the first teaser footage of Honnold, alone and very high up, working his way steadily up a crevice in the rock with nothing but his shoes and some chalk, and an extremely steady mind.

The entire climb took just four hours — something that climbers used to take days doing with the aid of ropes and partners.

A team of filmmakers which was led by one of Honnold's longtime climbing partners, Jimmy Chin, as well as Elizabeth Chai Vasarhelyi, filmed the entire climb for an upcoming National Geographic Documentary Films feature. (And I guess they used drones?) You can see some more photos via NatGeo now.

Previously: Insanely Brave Rock Climber Scaled El Capitan Without Any Ropes Or Safety Gear