The Ekiden de Montgeron is a spring relay race held in Montgeron, Essonne, south of Paris. Teams of six run the marathon distance, with each runner completing a specific leg: 5 km, 10 km, 5 km, 10 km, 5 km, and finally 7.195 km to reach the full 42.195 km. A shorter 10 km duo relay is also offered, where each runner covers 5 km. This event caters to beginners, families, club runners, and company teams, as well as competitive squads aiming for fast times.
The race begins along the Pelouse and proceeds through the flat paths of the Forêt de Sénart. This course is conducive to consistent pacing and efficient relay handoffs. The marathon relay course is FFA-labelled and qualifies for the French championships. ES Montgeron Athlétisme and the city co-organize the event, which includes a Corporate Challenge, a children's event combining running and throwing, refreshments for 10 km relay participants on the course, and food or drink for all finishers. Bibs have previously sold out quickly, indicating the race's local popularity among teams.