90 km du Mont-Blanc 2026

The 90 km du Mont-Blanc begins at 04:00 in Chamonix-Mont-Blanc, Haute-Savoie, France. This trail ultramarathon covers approximately 90 km with a 24-hour time limit and a UTMB Index category of 100K. Official race data lists it as 92 km with 6330 m of elevation gain, while UTMB Index data shows 90.20 km and 7000 m+. The essential point is clear: this is a demanding, steep mountain race, not merely a long trail run. This event is part of the larger Mont-Blanc race series in Chamonix, which includes shorter races: 10 km, 23 km, 42 km, the Km Vertical, and Le Duo Etoilé. A recent edition saw 1011 finishers, indicating a substantial field for such a challenging ultra. The competition at the front is also intense, with top male runners finishing around eleven hours. Notable female finishers have included Blandine L'Hirondel and Julie Roux.