Aidan Donnellan sits at a small table at Iron City Boulders, a sprawling complex of battleship gray climbing walls dotted with multicolored hand- and footholds in Lawrenceville. One side at a time, he pushes his long blond hair behind his ears and thinks a second or two before answering a question. Then he smiles.

“My first climb? That has to be the side of my house,” he said. “I remember grabbing onto nooks and crannies of the bricks. I was about 10. My parents were mad because they thought I’d damage the bricks.”

After scaling the walls of his Mt. Lebanon home, the high school senior said he started shimmying up light poles at the Mt. Lebanon Swim Center, playground equipment at school, basically everything and anything that would get him off the ground and rise above it all.

“I was always getting called out by the recess chaperones because they thought what I was doing was unsafe,” Donnellan said. “But I liked it so much that I kept on climbing everything.”

That’s when David Donnellan—Aidan’s dad and Mt. Lebanon’s recreation director—decided to take his son to a place where he could scale the heights safely.

“My wife suggested that I take Aidan to The Climbing Wall in Point Breeze,” David said. “After that visit, we were both hooked. Aidan found his passion in climbing. He’ll climb anything that’s in front of him.”

Right now, Aidan gets ready to grapple with the wooden boulder in front of him. After stretching to loosen up and shaking some chalk on his hands for a better grip, he places his left foot on a small black plastic hold and reaches for a hand hold higher up. He repeats the process until he’s nearly at the top of the 20-foot-tall wall, where he dangles in the air for a second or so before finishing the climb. After reversing the pattern a bit, he lets go of the holds and drops with a soft thud to the thick mats below.

In all, the climb took less than a minute.

At 5’ 11” and 145 pounds, Aidan might be the perfect body type for a climber. Long and lean, he seems to extend his arms like twin telescopes during the climb. And his light weight makes it easier to pull himself up the wall.

After a couple more climbs, he stops to explain what drives his obsession.

“It’s a very individual sport,” he said. “You’re not depending on anyone else. It’s just you and the wall. There’s a joy in being so exposed and knowing that the only thing keeping you from falling is you.”

Which brings up the matter of fear.

“Of course, I get scared sometimes,” Donnellan said. “You’re always going to be scared when you’re climbing.” To overcome his fears, Donnellan focuses on his breathing and the moves he’ll need to continue his ascent.

“I never think of falling,” he continued. “And I never look down.”

While he never looks down, Donnellan is looking forward. He’s enrolled at the University of Pittsburgh next fall to figure out his future away from climbing. Undecided as far as a major, he’s leaning toward environmental sciences—an almost natural selection for someone who spends a lot of time in close contact with the outdoors. When he’s not practicing or competing indoors, Aidan climbs real boulders and rock walls.

“Caring for the environment is a big part of rock climbing,” he said. “Climbers care about it because we’re so intimate with it. We help maintain trails, establish climbing areas and clean the walls of moss, dried-up lichen and other things, but only where we climb. We try to keep our impact on the land to a minimum.”

Along with being a good steward of the land, Aidan keeps himself in pretty good shape. He trains with his team three times a week at Iron City Boulders and drops by in between to lift weights and get in some cardio. The workouts build his endurance for the climbing competitions he enters. Though he’s advanced as far as regional and divisional finals, reaching the nationals might be his toughest climb.

At 18 years old, Donnellan is in his last season in the youth division of USA Climbing, the governing organization of climbing competitions in the United States. After that, he’ll be up against far more experienced adult climbers. But winning is secondary to the joys of climbing.

“Climbing is one of the most unique sports you can get yourself into,” Aidan said. “There’s always something new to learn. New places. New moves. New people. It’s really addicting and I’m always going to love it.”