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
Number withdrawal
Number collection for the 90km race will be by appointment only, at the EMC2 space on Place du Mont-Blanc (Chamonix):
- Thursday, June 25, 2026 from 9am to 9pm.
Runners must bring with them: photo ID and a race bag containing all compulsory equipment, to enable a timing chip to be fitted and equipment to be checked.
No race numbers will be issued to runners without their compulsory equipment and identity papers. No race numbers will be distributed on the night of Thursday to Friday, before the start of the race.
Compulsory equipment
- Cell phone in working order and with a subscription adapted to the countries crossed by the race (France and Switzerland).
- Photo ID card.
- Water supply of at least one liter.
- Waterproof jacket with hood (gore-tex type) adapted to your size.
- Warm second-layer garment (with long sleeves) adapted to your size.
- Headlamp or chest lamp with spare batteries.
- Survival blanket (140cm x 200cm).
- Whistle.
- Tumbler.
- Bowl and spoon.
- Cash.
Recommended equipment
- Cap.
- Tights.
- Gloves.
- Roll of straps.
Time barriers
The time limits given below are for guidance only. In the event of adverse weather conditions, and for safety reasons, the organization reserves the right to stop the event in progress or modify the time limits. All decisions will be taken by the race jury.
- La Flégère (km 18) : Start time of last wave + 4h30 of race.
- Le Buet feed station (km 28): Start time of last wave + 6h30 of race.
- La Villaz (km 35): Start time for last wave + 8h00 of race.
- Emosson refreshment station (km 40): Start time for last wave + 10h00 of race.
- Le Châtelard (km 44) : Start time for last wave + 11h00 of race.
- Ravitaillement du Tour (km 60): Start time for last wave + 15h15 of race.
- Les Bois feed station (km 69): Start time for last wave + 17h15 f race.
- Montenvers feed station (km 75): Start time for last wave + 19h45 of race.
- Plan de l'Aiguille refreshment station (km 81): Start time for last wave + 21h45 of race.
- Maximum race time - Chamonix finish (km 88): Start time of each wave + 24h00 of race.
If a runner arrives at a time barrier after the time barrier has been applied, he or she will be disqualified. The lower right-hand corner of the race number will be "cut out" by the station chief and the runner will be invited to return to Chamonix by his own means or by those provided by the organization. Should the runner wish to continue on the course, his or her number will be collected by the station chief and the runner will no longer be considered a participant in the Mont-Blanc 90km, and will therefore no longer be under the responsibility of the organizer. Anyone disrespecting the volunteers and members of the organization responsible for enforcing the time limits will be permanently banned from all Mont Blanc Marathon events.
Maximum race time
Runners crossing the finish line after the maximum race time will not be classified and will not be considered as finishers. This maximum time is calculated according to the start time of your wave.
90km du Mont-Blanc: maximum race time: 24h00
The organizers would like to draw runners' attention to the fact that, depending on the systems and settings used, GPX tracks may give different results for race distances and gradients.
