The Ultra-Trail du Mont-Blanc is a single-stage mountain ultramarathon that draws the world’s top ultrarunners. It’s an agonizing ~105-mile route that features over six miles of ascent around Mont Blanc Massif. We got an inside peek at the action (and the anguish). Consider this your introduction to UTMB, the World Series of ultrarunning.
A quarter past 2 a.m., Saturday — Courmayeur, Italy.
A few hundred paparazzi wait impatiently, speculating on when the first runners will arrive. They wait in one long line—armed with high-end mirrorless cameras, sipping mugs of instant coffee, wearing colorful, bulbous puffer jackets and headlamps—like a string of Christmas lights.
There’s palpable tension in the brisk mountain air surrounding the de facto halfway point of the race. Is this the year an American finally wins UTMB?
Even in the quietest part of the night, both sides of the paved path leading in and out of the gym-turned-aid-station are tightly packed. An hour ago at Lac Combal, the last timed checkpoint, the leaders were slightly ahead of course record pace. But that was early in the night.
Just a few minutes later we hear cowbells, perhaps a half-mile away, and the crowd begins jostling for a better view. By our rough calculations, they have gained even more time on the record.
News spreads up the steep mountain valley faster than the racers can run toward us. The heavyweight battle between the soft-spoken Spaniard Killian Jornet and the American flamethrower Jim Walmsley is as good as billed. The two favorites are just seconds apart, more than 10 minutes ahead of third place. It feels inevitable that one will win the race.
Half past 5 p.m., Friday — Chamonix, France
Nine hours earlier and on the other side of the border, we stand in a small parking lot, watching another star, Tim Tollefson, go through his kit one final time. Even from a distance, we can hear every enunciation of the booming loud speaker at the start line. As the race favorites walk down the blue carpet to the iconic arch at the center of town, their names and nationalities are announced in three languages, gradually building the crowd to a fever pitch.
After running the last five iterations of UTMB, Tim was careful to check every detail. The last American to make the podium, he knew that everything had to go right for a chance to repeat. Now, confident he had it all in place—poles, headlamp, spare jacket, water flasks brimming with a carbs-and-electrolyte mix—he hugged his mom before heading downtown with a handful of cameras in tow. For just this week in Chamonix, trail running feels like the center of the athletic universe.
Minutes later the gun goes off and the leaders sprint out ahead of the rest, hoping to avoid being tripped by the 2,300 runners behind them. The crowd, peering out of windows, filling grandstands, and lining streets, explodes into chants and song, wishing runners well as they begin one of the most grueling courses in the world.
9 p.m, Friday — Notre Dame de la Gorge
The sun sets before the leaders reach the last French aid station, Notre Dame, the site of a 13th-century church, at the base of a 7,900-foot pass. For centuries, travelers would stop to pray for safe passage before climbing the steep stone steps to Col du Bonhomme. Today, the route is lined with spectators, bonfires, and music, akin to the raucous crowds of the Tour de France.
We hike up a few hundred yards and don’t have to wait long until we see Jornet and Walmsley, both power hiking up the steep section. American Zach Miller, Spanish star Pau Capell, Frenchman Matheiu Blanchard, and British pro Tom Evans are not far behind. Despite three hours of racing already, all six look calm and relaxed. The crowd cheers loudly as they appear out of the darkness, offering motivation as the group departs into one of the most lonely sections of the course. From here, runners will go solo for five-plus hours until they reach their support crews at Courmayeur.
Quarter to 6 a.m., Saturday — Grand Col Ferret
After watching the top dozen pass through the gym in Courmayeur, we drive to Arnouvaz and hike up almost 2,000 feet to the Swiss-Italian border, reaching the col, the lowest point between two peaks—well before the sun rises. Here, we meet a few dozen others—a mix of race officials, mountain guides acting as medical support, and journalists covering the race—also waiting for the leaders. From the col, we see a long string of slowly moving headlamps down the valley. Soon enough the first few will reach us.
To many, the Grand Col is where the race really starts. Some even say it starts at Champex-Lac, 15 miles farther. Everything up to this point—63 miles and 21,500 feet of climbing—is just the warmup. Any real contender will be near the front when they reach the Grand Col, but with eight hours of racing ahead of them, a lot can (and will) happen. The three stout climbs remaining often make or break the day.
After waiting for a half-hour, a lone headlamp appears at the base of the final ridge, signifying that someone had broken free. This was the first time the two leaders were split by more than a handful of seconds. A few minutes later, Jim Walmsley, three-time winner of Western States, drops down the backside. He looks smooth and fresh. It’s hard for us not to imagine his path to victory, but we temper our optimism for the moment.
Quarter to 2 p.m., Saturday — Chamonix, France
After hiking down the Swiss side of the Grand Col, we grab a coffee and croissant, before racing to catch up with the leaders. I’ve slept less than an hour, but the excitement and added caffeine have me wired. The most venerated ultrarunners in the world were chasing a win, and currently on pace to finish in sub-20 hours, setting the course record.
Soon after we saw Walmsley at the col, he built a 15-minute lead, then began to cramp. Behind him, Jornet was caught by Blanchard, who quickly moved up from fifth to second. Over the next few miles they worked together to reel in the American, eventually passing him before reaching the iconic red church in Trient, 20 miles from the finish.
Jornet and Blanchard run together until the next major aid station in Vallorcine. At the start of the last climb, Jornet makes a move. He’s halfway up Col des Montets and has a three-minute gap. By the summit at La Flegere, he leads by almost 10 minutes. Walmsley, struggling to keep calories down, falls off the back, and eventually finishes more than an hour behind Jornet.
We watch all of this unfold on a massive screen right near the finish line, in a densely packed crowd of hundreds. The music blasts from speakers at the finish line and announcers hype up every step the leaders take. The energy is electric—unlike any race I’ve ever seen.
Despite our hope of an American finally winning UTMB, the joy of watching Jornet win for a record-tying fourth time, setting the course record by a large margin, is infectious. His final time: 19:49:30.
He’s welcomed into Chamonix like a king, calmly crossing the line while putting his hands in the air to thank the electric crowd.
If that doesn’t inspire you to ditch the tread for the trails, what will?
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