But his greatest challenge started at 4 years old when he was diagnosed with a rare eye disease called juvenile retinoschisis
. For almost 10 years, Weihenmayer was faced with an inevitable truth: One day he wouldn't be able to see the world around him.
By his freshman year in high school, Weihenmayer was blind.
"I wanted to be with my friends and going on dates," he says. "I was afraid that I wasn't going to be able to participate in life."
But his parents refused to let him sit on the sidelines.
"My dad would sweep me out into the world and I'd get beat up a little bit and shattered," he recalls. "And my mom would build me up and my dad would sweep me out again. And that's a hard thing to do as a parent."
Before losing his sight, Weihenmayer couldn't participate in physical sports because it would damage his retinas, making his sight get worse at a faster pace. In a way, going blind allowed him to start his life.
He joined the wrestling team and went all the way to the National Junior Freestyle Wrestling Championship in Iowa.
"Wrestling really changed my life because it was the first time as a blind person that I was a part of something bigger than me," Weihenmayer says.
He also learned how to rock climb.
"I remember loving rock climbing because it's a stable rock face. It's not moving, hopefully, and you're just feeling your way up the rock face," he says.
After graduating from Boston College, Weihenmayer moved to Phoenix to be a teacher. He spent every weekend rock climbing with the Arizona Mountaineering Club.
His quest for adventure began to take shape after he and a team of friends climbed Denali, the tallest peak in North America.
"I thought how amazing to make your life like this great adventure and just go around and be on every continent climbing the tallest peak," he remembers.
After scaling four of the seven summits, he set his sights on Everest.
"A lot of the Himalayan experts said the ice is so hard up high, you can't throw your ice ax down into the snow so you cannot stop if you fall," Weihenmayer says. "You can't think at high altitude. Above 26,000 feet, you're in the 'death zone' so your brain doesn't work very well. So it wouldn't be a good place for a blind person."
But he never lost hope.
"They were judging me on the basis of one thing that they knew about me and that was being blind. But they didn't realize that there are a dozen other attributes that contribute to whether you're a good mountaineer or not," he says.
Weihenmayer put together a strong team, received funding from the National Federation of the Blind and set out on his most dangerous and deadly expedition.
"You gotta keep an open, clear mind throughout the whole experience. You get beat down one day, just completely crushed, and you gotta wake up the next day and do it all over again," he says.
Despite his critics, in 2001, Weihenmayer became the first blind person in history to reach the summit of Mount Everest.
"You can't even believe it in a way that you're standing up there. You're with your team, and yeah, there might be a few tears. You hold your flag and you get your photos but then you have to turn around and get down," he recalls. "You gotta get down alive."
Weihenmayer not only made it down the mountain, he went on to climb the remaining seven summits in 2008.
Always seeking new adventures, Weihenmayer spent the next six years training to kayak the 277 miles of the Colorado River through the Grand Canyon.
"Sitting above a rapid knowing that in the next two minutes you're going through absolute insanity ... it was a very different experience from climbing," he says.
Weihenmayer used waterproof Bluetooth radios to communicate with his guide. He and nine other paddlers made it through the Grand Canyon in 20 days.
"I'm not just doing these things so I can prove that blind people can do this or that. That's kind of shallow," he says. "You do it because that's living fully."
Weihenmayer is using that mantra to help others. He co-founded the nonprofit No Barriers
in 2005 to help people overcome obstacles through educational programs, adaptive activities and transformative experiences.
"No Barriers is about really figuring out how to tap into whatever we've got inside of us and then build the tools and the community around us to break through barriers, live with purpose and be the person you're meant to be," he says.
Throughout his life, Weihenmayer has been featured in three documentaries
and written three books
: "Touch the Top of the World," "The Adversity Advantage" and "No Barriers," which will be available in February 2017.
The now 47-year-old, who lives in Colorado with his wife and two kids, also uses his story to inspire others through motivational speeches.
"It really takes this mindset of not being afraid to turn into the storm," he says. "In our lives all of us in a way are climbing blind."