Le sentier des chefs d'unités is a short trail race in Florac-Trois-Rivières, Lozère, starting at 09:30 and held in autumn. The primary distance is approximately 11 to 13 km, with the 11.2 km version featuring 463 meters of elevation gain. A 6 km option is also available for a shorter run.
The course crosses the Tarnon valley, passing beneath the Rochefort rock, presenting a compact mountain-valley trail rather than a flat town run. The race originated from the GRIMP National Training Center, a facility for specialist firefighters training in hazardous terrain rescue. The event grants access to this training ground for club runners, casual participants, athletes, nature enthusiasts, and intrigued local residents.