The Chamonix Trail Racing Scene You Might Not Know
Top photo: Adrien Colleur
When you think of Chamonix and trail running, there’s a certain set of races that very likely (okay, almost certainly) come to mind: UTMB® Mont-Blanc.
You’ve almost certainly heard of the Mont Blanc Marathon too, and maybe even the September race that feels like the coda to every trail running season, Trail des Aiguilles Rouges. (It’s a great event, by the way, and the proceeds support Chamonix’s trail running club, CMBM.)
All of that makes sense, of course, since Chamonix is often referred to as trail running’s world capital, and UTMB as the sport’s Super Bowl.
But under the radar, and often known to just us locals, there’s a lively and fun scene, the news of which often doesn’t extend beyond the high ridgelines that define the valley.
We thought we’d change that, just for a moment, courtesy of Ultra Montée des Posettes, a race organized by the energetic team at CMBM.
Ultra Montée des Posettes
The montée, or climb, is one of my favorite kinds of trail races– a true “concept” run. The start is at the base of the local gondola to Col des Posettes in Vallorcine– the high end of the somewhat tilted Chamonix valley, just a few kilometers from the Swiss border. Run the 710 meters up to the top of the lift, take a moment at the aid station (be sure to say hi to the ever-smiling former CMBM President, Federico Gilardi), then hop a ride down.
And repeat. For 2, 4, or 6 hours.
CMBM President Romaric Gauthier explained, “The idea for the race came from Dédé Bozon, a long-standing member of the club and part of an important family in Vallorcine. He wanted to create a sporting event that would also liven up the annual Vallorcine village festival. According to the two oldest competitors – 85 and 83 years old – the course was difficult but enjoyable!”
I’d wager my new ADV-12 you’ve never heard of Ultra Montée des Posettes. There’s no fancy web site and no marketing team behind it. All the same, hundreds of trail runners took part in the first edition in August 2025, nearly all of them from the Chamonix valley or nearby.
Local Competition
How local was it? Put it this way: How often do you get to run with your neighborhood organic dairy farmer? (That’s our friend Victor, from La Ferme de Vallorcine. And because it’s Chamonix, Victor is also licensed as a hiking, snowshoeing, and trail running guide.) Also running: Elie Guy, a well-known local builder from the valley, and Michel Poletti, co-founder of UTMB, who at age 71 was in fine shape and très rapide on the course– and will be among the 2,300 runners starting UTMB. I might have also been passed by his son David, one of the valley’s strongest runners, who finished fourth in the four-hour event.
There were a bunch of us from Run the Alps, too:
Carrie Craig, Partner and Finance Manager
Ed Monrad, one of our wonderful guides
Ella Hall, our Hub Manager
Emily Edwards, our US accountant
Emily Geldard, Partner and Head of Guiding
Marleen de Graff and Rob Pierpont, our friends, helpers, and all around Run the Alps groupies
Niko Viglione, our Race Finder Manager, and his partner Marcea Ennamorato
Sheridan Stride, our Chamonix Shop Manager
Adrien Colleur, a photographer for Run the Alps
And yes, yours truly was there too!
Together, our little crew ticked off 42 total laps, good for 30,240 meters, or 100,000 feet of climbing. (In the interest of showing off, I might have rounded up by a few feet here.) Notable congratulations to our photographer, Adrien, who landed in second place in La Montée à Déde. The one-lap vertical race closed out the day’s events, and Adrien ticked it off in a time of 31:00– just 16 seconds behind the winner!
Chamonix Trail Racing
The Ultra Montée des Posettes was put on courtesy of CMBM, Chamonix’s lively trail running club that has 270 members. The club organizes training sessions throughout the year, often in four tiers– elite racer, recreational runners, nordic walkers, and a youth section.
Here in Chamonix, one race doesn’t detract from another. It’s not a zero-sum game. It’s additive. And I love it all. When it comes to running on trails, it’s a big valley here, and there’s room for Ultra Montée des Posettes, Argentrail, Mont Blanc Marathon, Trail des Aiguilles Rouges, UTMB, Club des Sports and CMBM. Not to mention endless skyrunning routes, no shortage of guide books (yes, we have a favorite!) and dozens of trail running guides. And this time of year there are weekly trail runs from every brand under the sun.
In Chamonix, the trail running never really stops.
Thanks to all the volunteers at the Ultra Montée des Posettes. We loved it! And we’ll see you all next year!
More about CMBM and Ultra Montée des Posettes
