Grand Défi SEP 2026

The Grand Défi SEP includes a 10 km road race, a 5 km road race, two walks, and a 1 km children's race within Parc de Sceaux, a 184-hectare historic estate south of Paris. It takes place in Sceaux, Hauts-de-Seine, Île-de-France, in early November. The event funds research for multiple sclerosis, a neurological disease affecting over 115,000 people in France, and a primary cause of severe non-traumatic disability in young adults there. The routes are contained within the park, not a city-to-city course, making the setting a key attraction. Parc de Sceaux was designed by André Le Nôtre in the late 17th century and is a designated historic monument. The program accommodates more than just regular runners, offering short walks, races for children, bib pickup on-site, and affordable entry fees for all distances. Participants engage in a "Solidarity Challenge" as much as a race, with families, walkers, runners, and supporters uniting for a morning focused on a shared cause.