The Trail de la Mandallaz starts in La Balme-de-Sillingy, a village in Haute-Savoie near Annecy, with the Mandallaz mountain overhead and Lake Annecy visible. This spring trail-running event features mountain routes. The main options are the 11.1 km Trail à Une Tête, offering 560 m of elevation gain, and the 21.4 km Trail à Deux Têtes, with 1,070 m of climbing.
The shorter race, open to participants aged 17 and up, provides a challenging introduction for newer trail runners, featuring steep climbs, narrow descents, and a lake view. The longer race is for adults and includes more demanding ascents, technical terrain, flowing descents, the Tête de la Mandallaz, and the Goliettaz plateau. Runners navigate single-track paths, undulating forest trails, and scenic sections. One aid station is available on the short route, and two refreshment points are on the long one. Local involvement is key: shopkeepers, the municipality, marshals, clear signage, and a post-race buffet transform La Balme-de-Sillingy into a central point for the Haute-Savoie trail running season.