Grenoble, FRA ·
16 Jul - Jul 19, 2026
A full loop around Grenoble's four alpine massifs, from the Vercors to Belledonne.
The Ultra Tour des 4 Massifs is a demanding alpine ultra that circles Grenoble by crossing the Vercors, Chartreuse, Belledonne and Taillefer massifs. Starting and finishing in the city, it offers multiple formats from summit races to the legendary 170 km XTREM loop with over 11,000 metres of positive elevation.
The Ultra Tour des 4 Massifs, known as UT4M, is one of the toughest alpine ultras in France. Based in Grenoble, the event links the four great massifs that surround the city: the limestone plateaus of the Vercors, the wild ridges of the Chartreuse, the granite high country of Belledonne, and the rugged peaks of the Taillefer. Runners weave from city streets straight onto steep alpine trails, climbing past refuges, lakes and balcony paths that reveal the full sweep of the French Alps.
The format is unique in ultra running. Athletes can choose between summit races, single massif stages of 40 to 100 kilometres, multi day challenges, and the iconic UT4M 170 XTREM, a continuous loop of roughly 170 kilometres with more than 11,000 metres of positive elevation. Highlights along the way include the Moucherotte, the Chamechaude summit, the Croix de Chamrousse, the Lac Achard and the long technical descents back toward the Isère valley.
Held each July, the race draws a passionate community of alpine runners who come for the vertical, the high mountain atmosphere and the rare experience of finishing a world class ultra right in the heart of a major city. UT4M rewards strong climbers, careful pacing and a real taste for raw mountain terrain.