Famed tightrope walker Nik Wallenda is aiming to make history again on Sunday.
A year after Wallenda, known as "The King of the High Wire," became the first person to tightrope directly over Niagara Falls, he is attempting to cross over the Grand Canyon on his highest walk ever.
Discovery Channel is set to air the event live, during which Wallenda will walk 1,500 feet above the Little Colorado River, a height greater than the Empire State Building. That's more than 1,300 feet higher than his Niagara walk, which aired live on ABC in June 2012.
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During a recent visit to The Hollywood Reporter's Cover Lounge, Wallenda said that, as a child, he used to travel to the Grand Canyon with his family -- seven generations of the "Flying Wallendas" have performed on wires -- and had it on his list of places to conquer.
"No matter where I am, anywhere in the world, I’m always looking around for the next spot," he said. "What’s a cool spot to walk between? Just like Niagara Falls, this is something that’s been on my list a long time, and it’s going to be a dream come true on June 23rd."
For the Niagara walk, ABC required that he wear a harness, but Discovery has made no such demands.
"The risks are, I guess they’re greater in the sense that I was tethered over Niagara and that was not my choice," he said. "Actually that’s something that I was adamantly against and was very uncomfortable with. I’d never worn a tether up until that point. ... The risks are definitely grand no matter where I walk, but this one is 1,500 feet up, 1,400 feet across and a lot of unknowns as far as wind, direction and speed."
On June 6, Wallenda and his team set up a training camp to simulate the conditions of walking over the Grand Canyon (the walk will take place in a remote section operated by the Navajo Nation Parks and Recreation).
"We’ll re-create those winds so that I’m prepared, probably more mentally than physically," Wallenda said. "Mentally it’s a lot more draining than physically. I’ve done it my entire life and the physical part comes fairly naturally. The mental part is always something that I have to work on."
As for what he might do to top himself, Wallenda said he has a "long bucket list." He's already walked from one state to another in the U.S. and from U.S. to Canada.
"I would love to walk from one continent to another," he said. "Over in Turkey, I can walk from Europe to Asia over the Bosphorus."
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But he demurs when asked if it's hard to find new challenges to top the previous ones.
"I don’t know if it’s about topping myself, but it’s about carrying on a legacy that’s lasted over 200 years," said Wallenda.
That doesn't mean he's pressuring his kids -- ages 15, 12, and 10 -- to follow in his footsteps. While the trio all have already walked on wires -- the family has wires in their backyard -- he's never forced them to practice.
"They play on the wire, but as of right now, none of them want to carry it on," he said. "One wants to be a doctor, one wants to be a scientist and one wants to be a veterinarian, and they have my blessing. Just like I think with any parent you want your kids to fulfill their desires or their hearts and that’s my feeling as well. If they don’t choose to carry this on, I’d probably sleep a little better actually if they were in college."
Wallenda's book, Balance: A Story of Faith, Family, and Life on the Line, hit bookstores earlier this month. In it, he writes about the challenges he's faced as well as his faith and what role that's played in his life; he said he hopes readers will be inspired by his message of never giving up.
Skywire Live With Nik Wallenda airs live starting at 8 p.m. ET/5 p.m. PT on Sunday, June 23 on the Discovery Channel. Check back Sunday for more of THR's interview with Wallenda.