28th June 2024


04:00 am


92 km

Difference in height

6330 m +/-



The Mont-Blanc 90 km race has become legendary in the Chamonix Mont-Blanc Valley. With its 92km and 6330 meters of vertical drop, it has been recognized as one of the most technical trail races in France. Although the route uses only hiking trails, these are sometimes narrow and breathtaking. Despite its difficulty, this race is one of the most beautiful!

Some sections of the route take place exclusively in the snow and runners evolve very frequently between 2000m and 2500m of altitude, which requires a certain acclimation. Weather can change rapidly in mountains (wind, precipitation, hot and cold) and running at night can sometimes increase the sensation of difficulty.

To participate to this race, it’s recommended to have a good mountain race experience, to be comfortable on any ground and to be autonomous for several hours. We draw your attention to the fact that a runner with no UTMB performance index higher than 450 points has very little chance to finish the race. In that case, it’s more recommended to participate in another race of Mont-Blanc Marathon.

Date : 28th June 2024
Start : 04:00am
Waves : 2 waves of start
Distance : 92 km
Distance of heights : 6330m D+/-

ULTRA TRAIL in semi-autonomy
Start to ‘Espoir’ Category
Limited to 1000 runners.
Maximum time : 25 hours 
8 full refreshment points
1 refreshment point at the finish

Bib collection by appointment from Thursday June 27th from 9am to 9pm on Place du Mont-Blanc.

During the delivery of the bibs of the Mont-Blanc 90KM, runners will have to present a photo ID and their race bag including all the mandatory equipment for equipment inspection. Thanks to this, the organisation will be allowed to put a chronometric chip on them. No bib will be given to runners who don’t have their bag including all mandatory equipment.

No race bibs distributed on Friday morning before the start of the race.

  • Mobile phone. It must work and have a subscription adapted to the countries (France and Switzerland). 
  • A reserve of at least 1 litre of water.
  • Waterproof and windproof jacket with hood (gore tex type) adapted to your size.
  • Clothing hot of second layer with long sleeve adapted to your size.
  • Headlamp or chestlamp with spare batteries.
  • Survival blanket (140cm x 200cm).
  • Whistle.
  • Bowl and spoon
  • Personal cup.
  • A photo ID.

The time restrictions indicated below are given as an indication, they may be modified if necessary for the safety of the participants. In case of bad weather, and for security reasons, the organisation keeps the right to stop the event in progress or to change the time barriers. Any decision will be taken by the trail committee.

The arrival of a runner on a time barrier outside the deadline implies his disqualification. The lower right corner of the bib will be “cut” by the person in charge and the runner will be invited to use public transport to return to Chamonix. If the runner wishes to continue the race, his bib number will be given to the person in charge and the runner will no longer be considered as a participant in the Mont-Blanc 90 km, so he will no longer be under the responsibility of the organiser.

Anyone who doesn’t respect the volunteers in charge of this function will be banned from racing permanently on all events of the Mont Blanc Marathon.

  • Planpraz (km 12) : start time of the last wave + 3h30 of race.
  • La Flègère (km 18) : start time of the last wave + 4h30 of race.
  • Refreshment of Buet (km 27) : start time of the last wave + 6h30 of race.
  • La Villaz (km 38) : start time of the last wave + 9h00 of race.
  • Refreshment of Emosson (km 43) : start time of the last wave + 11h00 of race.
  • Le Chatelard (km 47) : start time of the last wave + 12h00 of race.
  • Refreshment of Tour (km 62) : start time of the last wave + 16h15 of race.
  • Refreshment of Les Bois (km 72) : start time of the last wave + 18h30 of race.
  • Refreshment of Montenvers (km 78) : start time of the last wave + 21h00 of race.
  • Refreshment of the refuge du Plan de l’Aiguille (km 83) : start time of the last wave + 23h00 of race.


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 Marathon Clips 

Réalisation : Cybergraph – 2023.