90km: an epic race
90km du Mont-Blanc
With a distance of 92 km and 6330m of elevation gain, the 90km du Mont-Blanc is recognized as one of the most technical trails over the French landscape. Although the course runs exclusively on hiking trails, they can be sometimes narrow and airy.
Some sections of the route are exclusively snow-covered, and runners frequently find themselves at altitudes 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 feeling of difficulty of a passage.
To take part in this race, it is therefore recommended to have good mountain running experience, be comfortable on all types of terrain, and be self-sufficient for several hours. Please note that a runner with an UTMB index inferior to 450 points has very little chance to finish the race, so we recommend you to register for another Mont-Blanc Marathon race.
Race info
92km semi-autonomous ultra trail race
6330m D+/-
Open to Espoir category and above
Limited to 1,000 runners
2 starting waves
Maximum time: 25 hours
8 full feed stations + 1 finish feed station
Bibs pick-up
Bibs pick-up for the 90km race will be possible by appointment only, at the EMC2 space on Place du Mont-Blanc (Chamonix):
- Thursday, June 26, 2025 from 9am to 9pm.
Runners must present photo identification and their race bag, including all mandatory equipment, to enable a timing chip to be fitted and equipment to be checked.
No bibs will be issued to runners without their compulsory equipment and identity papers. No bibs will be distributed during the night from 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 can be modified in the case of bad 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 Flègère (km 18) : Start time of last wave + 4h30 of race.
- Le Buet feed station (km 27): Start time of last wave + 6h30 of race.
- La Villaz (km 38): Start time for last wave + 9 hrs race.
- Ravitailissement d'Emosson (km 43): Start time for last wave + 11:00 race.
- Le Chatelard (km 47) : Start time for last wave + 12:00 race.
- Ravitaillement du Tour (km 62): Start time for last wave + 16:15 race.
- Ravitaillement des Bois (km 72): Start time for last wave + 18:30 race.
- Montenvers feed station (km 78): Start time for last wave + 9:00 pm race.
- Plan de l'Aiguille refreshment station (km 83): Start time for last wave + 23:00 race.
- Maximum race time - Chamonix finish (92km): Start time of each wave + 25h00 race.
A runner arriving at a time barrier point, after the time barrier has been applied, 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. 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 responsible for enforcing the time limits will be 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 therefore not considered as finishers. This maximum time is calculated according to the start time of your wave.
90km du Mont-Blanc: maximum race time 25h00
The organizers remind racers that, depending on the systems and settings used, GPX tracks may give different results for race distances and elevation gains.
