The 50 km Sri Chinmoy is a small ultramarathon in Paris, run in the Bois de Vincennes from Pelouse de Reuilly near Porte 13. Participants repeat a flat 1,983-metre paved loop through wooded parkland. The 50 km race starts late in the morning and has an 11-hour limit. The event also includes a 100 km option with a 21-hour limit, meaning the day is structured around steady lap running rather than a point-to-point course.
The loop format ensures runners receive frequent support: aid is available every lap, offering water, energy drink, fresh fruit, and dried fruit. Lap counting is managed for each participant, and a clock displays the time at every circuit, important on a course with many repeats. The field is capped at 150 runners; a recent edition had 127 participants, giving it the feel of a focused club ultra rather than a crowded city race. Sri Chinmoy organizes the event, providing changing rooms, toilets, medical cover, soft music at the venue, trophies for category winners, and a diploma, souvenir, and finish meal for every runner.