On June 23, 2013, 34-year-old aerialist Nik Wallenda becomes the first person to walk a high wire across the Little Colorado River Gorge near Grand Canyon National Park in Arizona. Wallenda wasn’t wearing a safety harness as he made the quarter-mile traverse on a 2-inch-thick steel cable some 1,500 feet above the gorge. In June of the previous year, Wallenda, a member of the famous Flying Wallendas family of circus performers, became the first person to walk a tightrope over Niagara Falls.

Nik Wallenda learned to walk on a wire as a young boy, and made his professional debut as an aerialist at age 13. He went on to set a number of Guinness World Records, including the longest tightrope crossing on a bicycle and the highest eight-person tightrope pyramid. In 2011, Wallenda hung from a high-flying helicopter above Branson, Missouri, by his teeth. That same year, he and his mother successfully completed the high-wire walk in Puerto Rico that had killed Karl Wallenda.

On June 15, 2012, Nik Wallenda became the first person to walk directly over Niagara Falls on a high wire. He crossed an 1,800-foot-long, 7-ton wire from the U.S. side of the falls to the Canadian side at a height of around 200 feet in about 25 minutes. Because the event was televised around the world, broadcast officials required the famous funambulist to wear a safety tether in case he fell.

The following June, Wallenda made his Grand Canyon traverse. Wearing jeans and a T-shirt and holding a 43-pound balancing pole, he prayed out loud as he walked untethered across a 1,400-foot-long, 8.5-ton cable suspended 1,500 feet above the Little Colorado River. It was the highest walk of his career up to that point, and he completed it in just less than 23 minutes.