Mont Blanc Marathon: dates, route, pricing and mandatory gear
Written by Victor Michel — history enthusiast and passionate alpinist based in Chamonix. Publié le 16 juillet 2026
The Mont Blanc Marathon, held every year in late June in Chamonix by the Chamonix Sports Club (CSC, founded in 1905), brings together around 10,000 runners across 8 trail races, from the children's Mini-Cross to the 90 km. The next edition takes place from June 24 to 27, 2027.
À retenir
- Next edition: June 24-27, 2027 in Chamonix
- 8 races: 90 km, 42 km, 23 km, 10 km, Vertical KM, Duo Étoilé, Young Race, Mini-Cross
- 2026 reference pricing: from free (Mini-Cross) to €140 (90 km)
- Lottery entry for the 90, 42 and 23 km; direct registration for the 10 km, Vertical KM and Young Race
What is the Mont Blanc Marathon?
Organized by the Chamonix Sports Club, a nonprofit founded in 1905, the Mont Blanc Marathon is one of the largest trail running events in France, with around 10,000 participants each edition. Unlike the UTMB, which loops the entire massif over several days and countries, the Mont Blanc Marathon offers shorter formats (from 800 m to 90 km), concentrated in the Chamonix valley, and runs in late June rather than late August.
Next edition: dates and program
The next edition takes place from June 24 to 27, 2027. For reference, the 2026 edition followed this 4-day structure: Thursday, bib collection; Friday, 90 km start at 4:45 am and Vertical KM start at 4:00 pm; Saturday, starts for the 23 km (7:00 am), 10 km (10:30 am), Mini-Cross (from 8:30 am), Young Race (7:00 pm) and Duo Étoilé (7:30 pm); Sunday, 42 km start at 7:15 am (elite women at 6:45 am). The detailed hourly program for the 2027 edition is not yet published at the time of writing — check the official site marathonmontblanc.fr ahead of race day.
Pricing and registration: the smart move
Registration for the 90, 42 and 23 km goes through a lottery, with a priority order: Chamonix valley residents committing to public transport, then train/bus commitment, then the general lottery. The 10 km, Vertical KM, Young Race and Mini-Cross register directly, without a lottery. Smart move: the 10 km and Vertical KM offer preferential pricing until March 31 (€32 and €37 versus €40 and €45 afterward) — no reason to wait for these two races. The Mini-Cross is free. The 23 km and Vertical KM bibs also grant a free lift ticket back down to Chamonix, a real time and money saver after finishing at Planpraz.
| Race | Distance | D+/D− | 2026 reference fee | Runner limit |
|---|---|---|---|---|
| 90 km du Mont-Blanc | 88 km | ≈ 6,200 m | €140 | 1,000 |
| 42 km du Mont-Blanc | 42 km | 2,540 m | €80 | 2,300 |
| 23 km du Mont-Blanc | 23 km | 1,680 m / 870 m | €50 | 2,000 |
| 10 km du Mont-Blanc | 10 km | — | €32 then €40 | — |
| Vertical KM du Mont-Blanc | ≈ 3.8 km | ≈ 1,000 m | €37 then €45 | — |
| Duo Étoilé | — | — | €85 / team | — |
| Young Race | — | — | €30 | — |
| Mini-Cross | 800 m to 3 km | — | Free | — |
The routes: profiles and checkpoints
42 km du Mont-Blanc — profile and aid stations
| Checkpoint | Km | Cutoff (from last wave's start) |
|---|---|---|
| Le Tour aid station | 13.5 km | + 2h45 |
| Vallorcine aid station | 23.5 km | + 5h30 |
| La Flégère aid station | 34.2 km | + 8h30 |
| Finish — Chamonix | 42 km | + 10h (maximum cutoff) |
23 km du Mont-Blanc — profile and aid stations
| Checkpoint | Km | Cutoff (from last wave's start) |
|---|---|---|
| Montroc aid station | 11.4 km | + 2h30 |
| La Flégère aid station | 18.4 km | + 4h30 |
| Finish — Planpraz, Chamonix | 23 km | + 6h (maximum cutoff) |
90 km du Mont-Blanc — profile and aid stations
| Checkpoint | Km |
|---|---|
| La Flégère | 18 km |
| Buet | 28 km |
| La Villaz | 35 km |
| Emosson | 40 km |
| Le Châtelard | 44 km |
| Le Tour | 60 km |
| Les Bois | 69 km |
| Montenvers | 75 km |
| Plan de l'Aiguille refuge | 81 km |
| Finish — Chamonix | 88 km (24h maximum cutoff) |
Mandatory gear
Mandatory gear is checked at bib collection: without the complete kit in your bag, no bib is issued. The base list is common to the semi-autonomous races (23, 42 and 90 km), with additions depending on the forecast.
Base list
- Charged, functional mobile phone
- Water reserve: 1 L minimum at the start (raised in case of forecast heat)
- Waterproof jacket with hood, Gore-Tex-type membrane, sealed seams
- Headlamp or chest lamp with spare battery
- Survival blanket: 140 cm × 200 cm minimum
- Whistle
- Personal cup: 15 cl minimum
- Food reserve
Addition for cold weather
- Long-sleeve technical top
- Lightweight gloves
- Warm hat or neck gaiter
Addition for hot weather
- Cap or wide-brimmed hat
- Sunscreen
- Sunglasses
À lire ensuite
FAQ
When is the Mont Blanc Marathon 2027?
From June 24 to 27, 2027, in Chamonix. The detailed hourly program for each race is published by the organization in the months before the event.
What races does the Mont Blanc Marathon offer?
Eight events: the 90 km, the 42 km, the 23 km, the 10 km, the Vertical KM, the Duo Étoilé (team), the Young Race and the Mini-Cross (children's races from 800 m to 3 km).
What is the route and elevation gain of the 42 km du Mont-Blanc?
42 km for around 2,540 m of combined elevation change (D+/D−), with fast-rolling trails in the first part then the technical slopes of the Aiguillette des Posettes, the course's main difficulty, before finishing in Chamonix.
What is the elevation gain of the 90 km du Mont-Blanc?
About 6,200 m of combined elevation change over 88 km, with 9 intermediate checkpoints (La Flégère, Buet, La Villaz, Emosson, Le Châtelard, Le Tour, Les Bois, Montenvers, Plan de l'Aiguille refuge) before finishing in Chamonix, with a maximum cutoff of 24 hours.
How much does registration for the Mont Blanc Marathon cost?
For reference (2026 pricing): €140 for the 90 km, €80 for the 42 km, €50 for the 23 km, €32 to €40 for the 10 km, €37 to €45 for the Vertical KM, €85 per team for the Duo Étoilé, €30 for the Young Race, and free for the Mini-Cross.
How do you register for the Mont Blanc Marathon?
The 90, 42 and 23 km are allocated by lottery, with priority given to Chamonix valley residents, then to runners committing to arrive by train or bus. The 10 km, Vertical KM, Young Race and Mini-Cross register directly, without a lottery, generally in November.
What mandatory gear is required for the Mont Blanc Marathon?
A base common to the semi-autonomous races: charged phone, 1 L of water minimum, waterproof jacket with hood, headlamp with spare battery, survival blanket (140 × 200 cm minimum), whistle and personal cup. Additions are required depending on the forecast (warm layer and gloves in cold weather; cap, sunscreen and sunglasses in hot weather).
Is the Mont Blanc Marathon accessible to beginners?
The 10 km and the Young Race suit a beginner audience. The 23 km and 42 km are classed as semi-autonomous and require prior mountain running experience. The 90 km, with its 24-hour cutoff and significant elevation change, is aimed at experienced ultra-trail runners.
What is the difference between the Mont Blanc Marathon and the UTMB?
Both are held in Chamonix but by different organizations and at different times of year: the Mont Blanc Marathon (Chamonix Sports Club, late June, formats from 800 m to 90 km) precedes the UTMB (late August, up to 300 km for the PTL, a full loop of the massif across several countries). See our dedicated guide to choose between UTMB, CCC, TDS, OCC or MCC.
Can you use mechanical lifts to descend during the event?
Yes, for the 23 km and the Vertical KM: the bib acts as a free transport pass to descend to Chamonix via the mechanical lifts after finishing at Planpraz.