Le Défi de Fort-l'Ecluse 19 km 2026

Le Défi de Fort l'Écluse is a trail race held in Léaz, a small commune in France's Auvergne-Rhône-Alpes region. The 19 km course includes 950 meters of elevation gain, making it a short, demanding mountain-style run instead of a flat road race. It typically takes place in mid-October, offering a 12 km option in addition to the main distance. The routes are situated near the Haut-Jura natural park, challenging runners with steep inclines, sustained off-road sections, and uneven terrain. The event is locally recognized as a well-attended trail running day, with the direct slogan “Sois Fort !” — “Be strong!” — reflecting the challenge participants face. The 19 km race is also listed as Trail XS within the 25-44 KmE category.