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MINTURN — Ben Donnelly basks in his creation, admiring a web of slings, carabiners and ropes strung between a trio of trees atop a towering cliff above this former mining and railroad town.

“This is my art,” he says. “It’s meticulous and beautiful and elegant. It’s a masterpiece.”

Far away, his friend Mauro Poletti’s arms slowly rise and fall as he tenderly steps on the 1-inch-wide webbing the pair have strung more than 1,200 feet between two landmark crags above Minturn. It’s the longest highline ever rigged in Colorado. The two expert highliners — slackliners who specialize in traversing barely-taut webbing strung across canyons and other spans — dreamed up the record-setting traverse a couple years ago. This week, they enlisted eight friends to rig the line, a task that took 10 arduous hours, not including the two-hour hike/scramble to the remote mountaintop.

“This is the cleanest, biggest gap I’ve seen in Colorado,” says Donnelly, an adaptive ski instructor and owner of Vail Pedicab. He remembers teaching kids to slackline in Minturn in the shadow of those iconic cliffs when he first moved to the Vail Valley almost a decade ago.

WATCH: Click below to see drone footage of Mauro Poletti and Ben Donnelly in action.

(Courtesy Zach Mahone)

The rigging is part of the art. First, they flew a drone to stretch a spool of 100-pound fishing line between the cliffs. They used that fishing line to pull parachute cord across. Then the paracord pulled a larger rope until a kilometer of webbing stretched across the gap. (That kilometer includes the mainline they are walking on and a looser backup safety webbing spooled around the mainline in case it fails. Everything in highlining is about redundancy, with backups of backups protecting the athletes.)

They used lasers to make sure their anchors were roughly even, both at about 9,800 feet. Instead of drilling into the rock, they anchored their line to trees and rocks, part of their leave-no-trace ethos.

Now Donnelly and Poletti hope they have two, maybe three weeks of daily highlining. They aren’t doing it for publicity, like the 600-foot highline that professional slackliners stretched across Eldorado Canyon in 2016 to help raise money for park trails. This is a passion project for highliners eager to practice their craft on a rare span.

Mauro Poletti walks across the highline he helped rig between two landmark crags above Minturn. (Zach Mahone, Special to The Colorado Sun)

The highline is ridiculously challenging. They count their falls as they labor to reach the other side, a feat of intense focus that can last an hour or more. Poletti has made it across four times, and on Wednesday, he reached the other cliff with only three falls, catching himself on the rope each time before he needed the leash tied between his harness and the line. That’s called a catch.

“Only three catches,” Poletti says as Donnelly arrives at the line Wednesday afternoon after pedaling down from the top of the Vail Mountain gondola to avoid the grueling hike up from the valley floor. “If I train hard for a couple more days I think I will send it. I’m so stoked on that crossing. I made it almost 200 meters without falling.”

Donnelly grew up with a paralyzing fear of heights. Then he saw superstar climber and highline pioneer Timmy O’Neill in the 2005 film “Return to Sender.”

“Timmy O’Neill and that movie changed my life. I got super inspired by it and I was like ‘A year from now, I am doing that,’” Donnelly says.

He learned how to slackline, rock climb and rig anchors. A year later, with his fear of heights obliterated, he rigged a 75-foot highline in North Carolina and crossed it without falling.

Ben Donnelly regains his footing on the highline he and friends rigged between two landmark crags above Minturn. (Zach Mahone, Special to The Colorado Sun)

Donnelly is quick to admit that he and his crew of pals in the Vail Valley are far from the state’s best highliners. They wonder if they will be able to make it across their highline without falling. Some of them fall 20, even 30 times as they make the crossing. (They keep meticulous count.)

It’s not just a physical challenge. They can walk on tiny strips of webbing for days.

“This one is more mental. I really don’t know if I can do it clean. It’s really horrifying out there. There’s a reason more people don’t do lines this long. You are just hanging in space out there,” said Donnelly, who flinches when he’s called an adrenaline junkie. “Adrenaline is my enemy. If you want to find your flow and succeed, adrenaline will not help you.”

The hormonal surge from adrenal glands fouls everything, he said. It increases the heart rate, quickens breathing and stresses muscles.

“When I’m on the line I’m always trying to keep everything calm and focused,” Donnelly says.

And that mental zone is a difficult place to occupy for 1,200 or so steps on a 1-inch wide piece of webbing flapping in the wind 400-feet above the trees.

“Very hard,” Poletti says. “The walk itself isn’t that hard. It’s just the endurance of walking the whole thing without falling. You have to be in the zone for so long.”

Mauro Poletti walks across the highline he helped rig between two landmark crags above Minturn. (Zach Mahone, Special to The Colorado Sun)

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