Many of us like a thrill now and again. Maybe a roller coaster, a scary movie, perhaps driving slightly over the speed limit. None of that is in the same universe, however, as what you're about to... See More
Many of us like a thrill now and again. Maybe a roller coaster, a scary movie, perhaps driving slightly over the speed limit. None of that is in the same universe, however, as what you're about to see. This is a guy who climbs sheer rock faces with zero safety equipment. Here's ABC's Neal Karlinsky. Reporter: Look closely. That red speck stuck to the wall defying death is Alex hunnel. No rope, no safety equipment, no turning back. It's hard not to be nervous, even terrified, looking straight down at him. He's an extreme free-climber, this time taking on Mexico's el candero luminoso. The fact that his life is suspended by a few toes, his fingerties, and concentration galore is mind boggling. You're sort of focused on what you're doing or our sort of empty and executing what you have to do. Reporter: He's a pretty mellow guy for someone who's putting his life on the line all the time. Here we are on the summit of Moses. We just had a biblical experience. It's snowing. Snowing right hard. The wrath of god rained down upon us briefly, epic snow storm. Reporter: Fear, danger, and death. The subjects everyone wants to know about drive him a bit nuts. All I want to, do climb without a rope, whatever, it looks crazy. Wow, you're on the edge of a cliff. But like seeing a photo like that doesn't give any indication of how likely I am to fall off. Know what I mean? It just shows if I did fall off it would be a disaster. Truckers do the same thing. If you veer off the road, if they lose concentration a few seconds and veer off the highway at 80 miles an hour, they will die. But do people consider that extremely risky? Like, no. Because the risk is quite small. You see it that way? You see the analogy to driving a truck down a highway? The thing is I see that all of life is an odds game. Like everything you do has risk. So, you know. I mean, I choose my risks carefully. Reporter: And he has. At 28, hanneld is easily regarded as perhaps the world's best mountain climber. He holds a number of speed records for climbing sheer faces in yosemite without ropes. But if you're going to see how he does it, you have to visit his office. The mountains. Pull yourself up. Yep, good, good. Reporter: I did, and contell you, climbing even a little with Alex is definitely a case of, it looks a lot easier than it really is. Wow, that was horrible. You did good. Happy to be alive? Yes, I'm happy to be alive. Keeping it alive, barely. Reporter: We tagged along with him and his good friend and fellow insanely talented climber seeder Wright. I'm the king of a world! Reporter: On a series of climbs. Perfect. Not too bad from here. Good. Oh, yeah. All right, summit one. Not a bad view. Yeah, good view, go. Reporter: Wright is no sidekick. He's an accomplished professional climber in his own right. But even he occasionally worries about Alex. He's an extremely accomplished athlete. But at the same time there's things he can't account for. Say a rock could break, a bird flies out of a crack or something. He's playing a game where the ultimate, you know, stake is to lose your life. Reporter: Hunneld insists he gets too much attention for what's called free soloing, going without ropes, arguing that 90% of his climbs are with ropes. But it's hard to argue with the impression people get watching a person cling ropeless to a mountain, something that seems to impossible to most of us, one slip and it's all over. Has your inner voice stopped you at certain times from going on? Have you had that voice that says -- For sure, for sure. There's tons is of things I've gone solo and decided not to, climbed to the bottom of things and I'm not feeling it, climbs down and gone home. Reporter: He's had moments frozen on a mountain, fear fighting along the toe hold. There's feeling sorry for yourself and like, I better pull it together because I'm standing on a blank face, you know. So I stood there for a minute being like, what have I done? Then I finished the climb. Reporter: Being a professional mountain climber means being a bit of a nomad. His sponsors pay him to climb the world's most beautiful mountains year round. He's even popped up in the occasional TV commercial for Citibank. When ease in the U.S. He lives and travels out of his van. It's a nice home. I got everything I need in here. I mean, I do have basically everything I own in here. Reporter: His life is at once extreme and extremely simple. With his endorsements, including northface, he makes a good living. But he says he spends virtually nothing on himself. I'm making a peanut butter and jelly tortilla wrap thing. Reporter: His fears he says are no different from the rest of us down on solid ground. I used to be quite scared of like speaking in public, things like that. I've kind of gotten over it because of this kind of stuff. Reporter: During our time together they were in the midst of a grueling 700-mile bike and climbing trip which included stops for haneld's charitable foundation, providing solar panels to native American homes without electricity. It's about as far from a 9 to 5 lifestyle as you can get. And the conqueror of mountains has no intention of slowing down. Is this a job you can retire from? People retire from this? Yeah, there are a lot of old climbers. You can go out in the mountains your whole life and just enjoy. It's awesome. I'm hoping to like retire with grandkids ask stuff. Reporter: I'm Neal Karlinsky for "Nightline" in monument valley, Utah. Coming up on "Nightline,"
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