France · Haute-Savoie
UTMB Ultra Trail Du Mont-Blanc
Distance
174 km
Date
August 28, 2026
Entry fee
479 EUR
€ / km
€2.75
The sport’s crown jewel: 170K around Mont Blanc—big altitude, global hype, and a finish that defines trail running.
Elevation and Terrain
Total Meters
9900m
D+/KM
56.9m/km
For context, the Tor des Géants 330 loop has 73 D+/km.
Avg Uphill Gradient
13.2%
Avg Downhill Gradient
-13.8%
Uphill gradient distribution
Route Profile
Analysed 2026-05-02Terrain breakdown
Terrain
Climbs
Top climbs
19.4 km · 1556 m gain
starts km 27 · avg 8.0% · max 40.2%
6.2 km · 834 m gain
starts km 80 · avg 13.6% · max 33.6%
7.3 km · 805 m gain
starts km 9 · avg 10.9% · max 28.7%
Top descents
9.6 km · 1258 m drop
starts km 71 · avg -13.1% · max -58.8%
8.5 km · 972 m drop
starts km 16 · avg -11.5% · max -36.3%
5.7 km · 943 m drop
starts km 46 · avg -17.0% · max -36.8%
The Ultra-Trail du Mont-Blanc (UTMB) is a 174 km trail race held in late August, and perhaps the most renowned trail race in the world.
The course gains 9,900 m over 174 km (56.9 m/km), starting and finishing in Chamonix and looping through Italy and Switzerland on the emblematic Tour du Mont-Blanc route.
Entry costs €479 (~€2.75/km), allocated by lottery — the race is perennially oversubscribed. The biggest climb rises 1,556 m — the 23rd largest single ascent of 385 European trail distances tracked. Just 13.6% of the course is flat — the 76th least-flat of 390 European trail distances. 16.89 km of uphill terrain exceeds 20% gradient. The top descent drops 1,258 m over 9.6 km with a max gradient of 58.78%.
Weather is notoriously variable: 2025 conditions included rain, wind, and snow at the high passes; historical DNF rates reach 35–42% in bad-weather editions.
Nearest airport is Geneva (GVA), approximately 87 minutes by car. [DTR: Airport to Start Transfer Time] Founded in 2003 by Catherine and Michel Poletti, the UTMB drew 2,500+ starters in 2025 with 1,665 finishers. It suits ambitious, highly qualified trail runners with deep alpine experience who want to run the race that defines the sport.
How hard is the UTMB 174km? (Course profile, climbs, and GPX data breakdown)
Q: How hard is the UTMB 174km? A: Very hard — though not the most extreme course in European trail racing by gradient data alone. The UTMB covers 174km with 9,900m of elevation gain (56.9m per km) within a 47-hour cutoff. The biggest climb rises 1,556m — the 23rd largest single ascent of 385 European trail distances tracked. Just 13.6% of the course is flat. 16.89km of uphill terrain exceeds 20% gradient. What pushes difficulty beyond the numbers: late-August weather swings, sustained night racing through three countries, and a competitive field drawn globally. Historical DNF rates reach 35–42% in bad-weather editions.
How do you qualify for and enter the UTMB lottery?
Q: How do you qualify for and enter the UTMB? A: Entry requires UTMB Running Stones accumulated through UTMB World Series qualifier races, plus a successful lottery draw. For the 2026 edition, pre-registration ran January 8–19; lottery results were announced January 22, with waiting-list outreach in early February. Check montblanc.utmb.world for the 2027 registration timeline. Entry fee is €479 per runner (includes a €1.50 environmental tax and €13 Friends of UTMB membership). The race is perennially oversubscribed — qualifying stones are a hard prerequisite, not a guarantee of entry.
What is the weather like at UTMB — and how bad can it get?
Q: What is the weather like at UTMB — and how dangerous can it get? A: Highly unpredictable. The UTMB runs late August across the Mont Blanc massif; conditions at high passes (2,500m+) can shift from sunshine to freezing rain and snow within hours. In 2025, conditions at high passes included rain, wind, and snow; warming huts were opened at summit sections to protect runners in distress. [Race Report: Matt Urbanski, Team RunRun, 2025] Full mandatory gear — waterproof jacket, thermal layers, emergency blanket — is required throughout. Historical DNF rates of 35–42% in bad-weather editions give context to the stakes.
How to get to Chamonix from Geneva airport for the UTMB
Q: How do you get to Chamonix from Geneva airport for the UTMB? A: Geneva airport (GVA) is approximately 87 minutes by car from Chamonix. Direct shuttle buses run from GVA to Chamonix — no car required. Lyon (LYS) and Milan Malpensa (MXP) are alternative airports at approximately 2.5–3.5 hours. UTMB race week transforms Chamonix into a global trail running festival; accommodation sells out months or years in advance. Book immediately on receiving lottery confirmation — do not wait.
Race files
Logistics
Nearest airport
Geneva (GVA) / Lyon (LYS) / Milan Malpensa (MXP)
Notes
Start: ~1.25–1.75 hrs (GVA) or ~2.5–3.5 hrs (LYS or MXP) to Chamonix / Public transport: excellent shuttles and buses from GVA plus trains via Geneva; car optional / Accommodation: very strong but expensive in Chamonix; book very early (race week)
