One more time.

Aspen unicyclist Mike Tierney keeps turning, turning, turning to meet the new challenges of riding on one wheel.

Tierney, a legend in the world of unicycling, stepped up into the genre of big-mountain riding, and he started riding Colorado’s mountain passes.

“When I found I could do long distances with big climbing, I started doing the Continental Divide crossings on dirt,” Tierney said in an interview with The Aspen Times.

The whole project of unicycling across the divide crossings all started right here in Aspen, Tierney said.

“I rode Independence Pass. It’s my home hill; my favorite hill,” Tierney said. “Once I conquered that one, it kind of surprised me that I could do it.”

Pedaling his big, 36-inch wheel to the summit of Independence Pass inspired him to look at other challenging rides.

“I looked mostly at the pavement rides first,” said Tierney, who started checking off passes — Berthoud, Loveland, Tennessee.

“Rabbit Ears (near Steamboat Springs), that’s one that I did pretty early on,” said Tierney, who first learned to ride a unicycle when he was a 10-year-old growing up in Arizona.

“A neighborhood buddy … we challenged each other to learn to ride a unicycle. So, we joined a club in Phoenix and learned to ride.”

But less than a year later, unicycling had rolled out of his interests.

“I got into bicycling. I got into skiing. I got into girls and other things,” Tierney said.

Fast forward 30 years.

Tierney’s wife Anne found some photographs of a young Mike Tierney riding a unicycle.

“She found one at a garage sale, and she gave it to me,” said Tierney, 54.

“I hopped right on it and rode off into the sunset,” Tierney said with his familiar chuckle. “I thought, ‘Oh my god, it’s been 30 years, and I still know how to do this.”

The year was 2001.

“That was enough to get me hooked again,” said Tierney, who graduated to a new, 24-inch unicycle.

“I rode around the block. Then, I rode the Rio Grande Trail,” Tierney said of his progression back into unicycling.

Then, he said, he saw a 36-inch wheel.

“I started going even farther, even higher,” said Tierney, familiar in Aspen as a 30-year veteran of the Aspen Highlands Ski Patrol.

“So then, I just started knocking the … Colorado passes off the list,” Tierney said.

The pavement passes behind him, Tierney went off road.

And, he said, he never stopped appreciating the beauty of each of his rides.

“I do like to stop and take pictures, enjoy the beauty,” Tierney said. “That’s one reason I do this; it gets me to places I’ve never been.”

There are about 80 total passes in Colorado.

“I’ve ridden about 50 of them,” he said. “And I’ve done 31 continental divide crossings.”

He recently crossed Argentine Pass, Colorado’s highest at 13,207 feet (near Keystone).

And, he reminded the cycling world, “the downhill is just as hard as the uphill on a unicycle.”

Tierney’s legend on the single wheel grew as he won the road race at the North American Unicycling Championships in Utah, riding on the course at Soldier Hollow that was used by the Olympic cross country ski racers.

He won his age group in the unicycling track events. And he was second overall in the cross country race just two hours after the unicycling road race.

Tierney, a year later, became the first unicyclist to complete the Iron Horse Bicycle Classic road race in southwest Colorado.

He rode the 50-mile route from Durango to Silverton, climbing two mountain passes in the San Juans — Coal Bank and Molas — on famed U.S. Highway 550.

Then, Tierney headed east to conquer Mount Washington on a unicycle.

En route, Tierney started to ride other big passes.

He climbed Beartooth Pass in Montana.

He limbed Smugglers Notch and the Appalachian Gap in Vermont.

He pedaled up Mount Lemmon and Mount Graham in Arizona.

He’s unicycled the White Rim Trail in Utah.

And, he’s ridden in Hawaii.

Tierney climbed Mauna Kea and Haleeakala.

He hopes to ride next in Europe. And he’s got a return trip to Hawaii in the planning stages.

“I want to go back to the big island, and I want to ride Mauna Loa … sea to summit,” Tierney said.

“I’d love to get to Europe. I sit and watch the Giro d’Italia and the Tour de France and the Tour of Switzerland, and I see these places to ride,” he said.

Tierney said Colorado has another tough climb.

“Pikes Peak … you can ride Pikes Peak now. That’s the toughest climb in the state,” he said after the road to the summit was paved all the way to the top.

He said he’ll tackle that challenge, along with any other he might encounter.

“This keeps me alive. It keeps me loving life … unicycling brings universal happiness,” Tierney said. “Everywhere I’ve ridden … here, Mexico, Europe … people smile when they see it.”

Oh, one more thing.

“I love the simplicity of it.”

dstrode@aspentimes.com