Trail des Causses

The Trail des Causses is a 40-kilometer trail race with 1,800 meters of elevation gain starting from Millau, in Aveyron. This event crosses the grands causses, those arid and spectacular limestone plateaus of the southern Massif Central, where deep gorges, vertiginous cliffs, and steppe-like landscapes compose a mineral decor of austere and fascinating beauty.

Millau, the start and finish town, is famous worldwide for its viaduct, an engineering masterpiece designed by Norman Foster, whose pylons rise 343 meters above the Tarn valley. But Millau is above all the gateway to the Grands Causses, a unique territory where limestone plateaus are cut by deep gorges carved by the Tarn, Jonte, and Dourbie rivers.

The Trail des Causses course is a succession of climbs from the valleys to the plateaus and vertiginous descents into the gorges. Runners climb onto the causses, those limestone expanses covered with short grass, boxwood, and juniper, where white stones reflect sunlight with dazzling intensity. The descents into the gorges, on trails carved into the cliffs, offer plunging views over rivers winding hundreds of meters below.

The 1,800 meters of elevation gain are concentrated in brutal climbs from the valley floors and equally steep descents. The terrain is demanding: sometimes very technical limestone trails, passages through lapiaz and scree, steep descents on unstable rocks, and exposed ridge paths. Heat can be a determining factor in summer, as the white limestone of the causses reflects light and heat with formidable efficiency.

The Causse Noir, the Causse du Larzac, and the Causse Mejean, which the course crosses or skirts, are worlds apart. These plateaus, between 700 and 1,000 meters altitude, are marked by drought and wind. The vegetation, adapted to these extreme conditions, is that of garrigue and steppe: lavender, thyme, boxwood, and juniper. The dolmens, menhirs, and tumuli scattered across the causses bear witness to human occupation dating back to the Neolithic.

Millau is also a top destination for outdoor sports. Paragliding, climbing, canoeing, and trail running attract athletes from around the world to this territory of spectacular relief. The Millau viaduct, crossed or skirted by the course depending on the edition, provides a major photographic moment.

Aid stations offer Aveyron specialties: Roquefort, aligot, farrous, and Marcillac wine. The atmosphere is sporty and convivial, reflecting the vitality of Aveyron's trail community. The Trail des Causses is an event that leaves its mark through the power of its landscapes, the technical demands of its trails, and the dazzling luminosity of its limestone horizons.

Trail des Causses is a 40 km trail race with 1,800 m of elevation gain, located in Millau, Aveyron. The next edition is scheduled for 4 October 2026.

Find all official information on the race website.