This Month in Photo of the Day: National Geographic Magazine Features

"It feels like I'm hovering in space," says Dean Potter, perched on a highline above Yosemite Falls. Gusting winds and blinding mist make it tough to balance on the inch-thick rope 2,600 feet above the valley, but a tether attached to his waist protects him from disaster.

See more pictures from the May 2011 feature story "Daring. Defiant. Free."

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