La Peyrinissime is a trail-running event held on a Saturday in Peyrins. The race center is located on Rue des Écoles, with the finish line at the town gymnasium. The schedule includes timed trail races, walking routes, and children’s runs, making the day suitable for more than just adult competitors. The primary timed races are the 5 km Tour d’Enfer, featuring 120 m of elevation gain, and the 11.2 km Peyrinight, with 340 m of elevation gain. Younger participants can choose from short races ranging from 0.6 km to 1.5 km. Walkers have access to 5 km or 11.5 km trail routes on similar terrain but without the competitive pressure.
The courses incorporate a variety of surfaces, including roads, paths, trails, meadows, woods, and other off-road terrain surrounding Peyrins. Sections of the route and the event base are situated within the village, but the event also leads participants into natural settings and across private land accessible only for the occasion. The timed races are intended for runners experienced in self-sufficient trail running, particularly the Peyrinight. For families, very young children can participate in untimed activities like Les petits loups and Les petits Bolides, while older children have the option of the Mini Traillers race.