Trail des Sources de l'Yvette - Le P'tit TSY - 10 km MN 2026

Le P'tit TSY is the 10 km race at Trail des Sources de l'Yvette, held in Lévis-Saint-Nom in France's Chevreuse Valley. The event takes place in September and attracts trail runners, hikers, and Nordic walkers. Starts are from the village center, in front of the multi-purpose hall on Route d'Yvette. The courses follow hilly paths leading toward the Yvette river's sources. Organizers characterize them as selective and technical, not simple flat circuits. In addition to the 10 km race, the program offers a 21 km trail, a 47 km trail, a 10 km hike or Nordic walk, and La Petite Trotte, an orienteering race for teams of two or three. Volunteers assist with preparation and on race day. Past photos, videos, and results document the event's local history.