Chris Kelly Conquers Compo Hill. Next: The Rockies.

With the temperature climbing toward the mid-90s on Saturday, Old Mill residents sought relief.

Some enjoyed cold drinks at the deli. Some sat under umbrellas on the beach. Some stayed indoors, the AC blasting.

No one thought of running up and down Compo Hill. Not one time — and certainly not 50.

No one, except Chris Kelly.

Chris Kelly is all smiles — after running up and down Compo Hill 55 times, in 90-plus heat.

The entrepreneur lives in Aspen, Colorado. He was visiting his mother Marion, who lives nearby. With a race coming up soon, he figured he’d get in a bit of training.

This is no ordinary race. The Leadville Trail 100 — set for August 20, just 5 days after his 40th birthday — is, yes, a 100-mile run.

But this is no ordinary 100-miler. Starting at 9,219 feet in the Colorado Rockies, and reaching a peak of 12,532 feet, its climbs and dips cover nearly 16,000 feet of elevation.

It begins at 4 a.m. it ends 30 hours later, whether you’ve finished or not. A thousand runners — chosen by lottery — start. Three hundred finish.

Chris’ goal is 25 hours. For that, he’ll earn a large belt buckle.

Chris’ workout was no ordinary training. He chose Compo Hill — from Old Mill Grocery up to the end of Buena Vista Drive, then back down — because it’s the steepest, toughest one around.

Chris Kelly, in action.

It was a grueling physical challenge — made even more difficult, because Chris strapped a vest filled with 2 500-ml water bladders, and pockets for food, sunscreen, etc. on his back, to get used to the weight.

But the Leadville 100 is a mental test as well.

So Chris tested himself that way too. He planned his 50 “laps” up and down the hill — equivalent to a full marathon, including the run to and from his mother’s house at Compo Beach — to be repetitive and monotonous. He wanted each one to be as close to the same time as possible.

He succeeded. His fastest time was 4:08; his slowest, 4:28.

Except, that is, for his final ascent and descent. After hours in the blazing heat, he covered that in a blazing 3:46.

“I’m more proud of my ability to focus, and hit those numbers consistently, than anything else,” he reports. (We spoke a couple of hours after he finished. He sounded as if he had just gotten up from an afternoon watching a Mets game.)

A few of Chris Kelly’s stats.

Chris had another goal: to do all 55 laps in 4 hours. He made it, with 2 minutes to spare.

His total time on Compo Hill was about 5 hours. He stopped from time to time at OMG, for water and bananas. The Leadville 100 also includes stops too, of course, for food, hydration and changes of clothes.

As the day wore on, word spread. People asked questions. Neighbors offered water. There were plenty of cheers.

There were refreshments too. Chris’s mother and children set up a lemonade stand nearby. They raised $457, which they’ll donate to UNICEF’s Ukrainian children’s aid.

Chris Kelly’s mother and children, at their lemonade stand.

As he ran, Chris invited anyone to join him. Go figure: No one did.

The Leadville 100 will not be Chris’ first rodeo — er, insanely long race. He’s done several marathons (his best was 2:44, twice, in Chicago and London). He’ll run both the New York and Tokyo marathons later this year.

And — oh, yeah — he also completed the Grand Canyon Rim-to Rim-to Rim. Those 47.5 miles include a descent of 9 miles, a 7-miles run across the floor, and  7 miles up a 15% – 20% grade. The temperature is over 100.

I got exhausted just typing that paragraph.

Why does he do it?

“The simple answer is: because you can,” Chris says.

“It’s possible, but not easy. It tests the outer boundaries of the human capability. You find all the human emotions out there on the course, at one time or other.”

And, Chris notes, “I live a privileged life in Aspen, just like people in Westport. To voluntarily put yourself in a position of real strain brings joy to the rest of your life. When you do this, you can appreciate every day as something special.”

He paused.

“This is what I do for fun.”

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