90km: an epic race
90km of Mont Blanc
Although the course is run exclusively on hiking trails, these are sometimes narrow and airy. Some sections of the route are exclusively snow-covered, and runners frequently run at altitudes of between 2,000m and 2,500m, requiring a certain degree of acclimatization. The weather can change rapidly in the mountains (wind, precipitation, heat/cold), and running at night can increase the sense of difficulty of a passage.
To take part in this race, it is therefore recommended that you have good mountain running experience, are comfortable on all types of terrain, and are self-sufficient for several hours. We would like to draw your attention to the fact that a runner with an UTMB index of less than 450 points has very little chance of finishing the race, so it is recommended that you take part in another Mont Blanc Marathon event.
Race info
88km semi-autonomous ultra trail race
6200m D+/-
Open to "Espoir" category and above
Limited to 1,000 runners
3 starting waves (4:45 / 4:55 / 5:05)
Maximum time: 24 hours
7 full refreshment points + 1 light refreshment point + 1 finish refreshment point
Race Bib Pickup
Race bibs for the 90km race will be available by appointment only at the EMC2 space located at Place du Mont-Blanc (Chamonix):
- Thursday, June 25, 2026, from 9:00 a.m. to 9:00 p.m.
Runners must bring the following: a photo ID and their race bag containing all required gear, so that a timing chip can be attached and their equipment can be checked.
No race bibs will be issued to runners who do not have their mandatory gear and identification documents. No race bibs will be distributed overnight from Thursday to Friday, prior to the race start.
Mandatory Equipment
- A working cell phone with a service plan suitable for the countries the race passes through (France and Switzerland).
- Photo ID.
- A water supply of at least 1.5 liters.
- A waterproof jacket with a hood (Gore-Tex type) that fits properly.
- Warm mid-layer clothing (long-sleeved) that fits properly.
- A headlamp or chest lamp with spare batteries.
- Emergency blanket (140 cm x 200 cm).
- Whistle.
- Cup.
- Bowl and spoon.
- Cash.
Recommended gear
- Beanie.
- Tights.
- Gloves.
- Roll of straps.
Time Cuts
The time limits listed below are provided for informational purposes only. In the event of adverse weather conditions, and for safety reasons, the organizers reserve the right to stop the race in progress or to modify the time limits. Any decision will be made by the race jury.
- La Flégère (km 18): Start time of the last wave + 4 hours and 30 minutes of race time.
- Buet Aid Station (km 28): Start time of the last wave + 6 hours and 30 minutes of race time.
- La Villaz (km 35): Start time of the last wave + 8 hours into the race.
- Emosson Aid Station (km 40): Start time of the last wave + 10 hours of racing.
- Le Châtelard (km 44): Start time of the last wave + 11:00 into the race.
- Le Tour Aid Station (km 60): Start time of the last wave + 15 hours and 15 minutes into the race.
- Les Bois Aid Station (km 69): Start time of the last wave + 17 hours and 15 minutes into the race.
- Montenvers Aid Station (km 75): Start time of the last wave + 19h45 into the race
- Plan de l’Aiguille Refuge Aid Station (km 81): Start time of the last wave + 21h45 of race time.
- Maximum race time – Chamonix finish (88 km): Start time of each wave + 24 hours of racing.
If a runner arrives at a time cut-off after that cut-off has been enforced, they will be disqualified. The lower right corner of the race bib will be “cut off” by the checkpoint manager, and the runner will be asked to return to Chamonix by their own means or via transportation provided by the organization. If the runner wishes to continue the course, their race bib will be collected by the checkpoint manager, and the runner will no longer be considered a participant in the 90 km Mont-Blanc race; they will therefore no longer be under the organizer’s responsibility. Anyone who shows disrespect toward volunteers or members of the organizing committee responsible for enforcing the time limits will be permanently banned from all Mont-Blanc Marathon events.
Maximum Race Time
Runners who cross the finish line after the maximum race time will not be ranked and will therefore not be considered finishers. This maximum time is calculated based on the start time of your wave.
90km du Mont-Blanc: Maximum race time: 24:00
The organizers would like to remind runners that, depending on the systems and settings used, GPX tracks may yield different results regarding race distances and elevation gain.
The Gift That Makes a Difference
This year, the 90km du Mont-Blanc finisher’s gift has been replaced with a gift that will help you maximize your chances of finishing!
In an effort to increase your chances of finishing by reducing potential stomach issues (the main cause of race dropouts), the organizers have decidedto offer each participant free access to a nutrition plan specially designed for the 90km du Mont-Blanc.
This platform was developed by a young Chamonix native, Baptiste Ellmenreich, who is also an elite ski mountaineering and trail runner, passionate about the mountains and peak performance. His expertise has made it possible to create a nutrition plan tailored to the race’s aid station offerings, while taking into account your fitness level or estimated finish time to best support you in managing your race.
Goal : to optimize your nutrition strategy during the race to maximize your chances of crossing the finish line of the 90km race.
