What to Expect at UTMB Week in Chamonix
Every year at the end of August, Chamonix becomes the centre of the trail running world. UTMB week — the Ultra-Trail du Mont-Blanc — draws tens of thousands of visitors to the valley for a week of racing, atmosphere and alpine spectacle that is unlike anything else in the sport.
Whether you are running one of the races, supporting a friend, or simply curious about what all the fuss is about, this guide covers everything you need to know.
What is UTMB?
UTMB is a series of ultra-trail races held across the Chamonix Valley at the end of August each year. The flagship race, known simply as the UTMB, is a 170km loop around the Mont Blanc massif, crossing through France, Italy and Switzerland, with around 10,000 metres of elevation gain. It is widely regarded as one of the most prestigious ultra-endurance events in the world.
But the UTMB is not a single race. Race week includes seven events of varying distances, from the 40km MCC to the extraordinary PTL, a 300km team challenge with no fixed route. Together they bring close to 10,000 runners to the valley from across the globe.
The race schedule
UTMB week typically takes place during the last week of August. The week builds progressively, with the PTL departing on Monday morning and the main UTMB race starting on Friday evening from the Place du Triangle de l'Amitié in the centre of Chamonix. The OCC (57km) and CCC (100km) races take place on Thursday and Friday respectively, and the week closes with the final finishers of the 170km race crossing the line on Sunday.
For spectators, the finish line area in central Chamonix is the heart of the action throughout the week, with runners arriving around the clock. The atmosphere in the final kilometres is extraordinary, regardless of when you are there.
What is the atmosphere like?
Chamonix during UTMB week is a different town. The streets fill with runners, crews, brands and supporters from all over the world. The race village, the finish line, the cafés and bars around Place du Triangle de l'Amitié are constantly alive with energy. Elite athletes run right through the centre of town. Crowds gather at all hours to cheer finishers home.
For those who enjoy sport, mountains and the kind of atmosphere that only a truly global event generates, it is an exceptional week to be in the valley. Even visitors with no connection to trail running often find themselves caught up in it.
Where to watch
The best place to experience the races is at the finish arch on Place du Triangle de l'Amitié in central Chamonix. Every race throughout the week finishes here, and both the PTL and the main UTMB start from the same square.
For those who want to get out on the course, the trails around Argentière offer great vantage points during several of the races, without the crowds of the town centre. Argentière sits naturally on or close to several race routes and provides a quieter way to experience the event. For more on why Argentière is a great base during the week, read our guide on why to choose Argentière for your stay.
Practical things to know
Chamonix gets extremely busy during UTMB week. Accommodation books up many months in advance, sometimes over a year ahead for the best options. If you are planning to come, booking early is essential.
Traffic and parking in the town centre can be challenging. Staying in Argentière, just a short drive from Chamonix, gives you easy access to the atmosphere while being away from the busiest parts of the valley. The valley's bus network also runs regularly between villages throughout the week.
The weather at the end of August can be warm during the day but cold and unpredictable at altitude. If you plan to go out on the trails to watch the races, bring a warm and waterproof layer.
Staying at Les Rives d'Argentière during UTMB week
For teams, brands, athlete groups or private parties looking for a base during UTMB week, Chalet Ardoise at Les Rives d'Argentière offers a private and comfortable setting in Argentière, with 5 bedrooms and 5 bathrooms sleeping 12 across 200m², and access to the outdoor pool, hammam, sauna and a private hot tub. Close to the action, but away from the intensity of the town centre.