Les 40 Bosses
Saint-Leu-la-Forêt, France • 6-7 Dec 2025
The Les 40 Bosses will take place in Saint-Leu-la-Forêt from Saturday 6 December 2025 to Sunday 7 December 2025. You can run between 10 and 120 kilometers. Visit the organization's website for the most recent information.
Race information
UTMB 20K
UTMB 50K
UTMB 100K
UTMB 100M
120 km
5500 m+
120 Km – 5500m D+
75 km
3300 m+
75 Km – 3300m D+
45 km
2100 m+
45 Km – 2100m D+
20 km
900 m+
20 Km Nocturne – 900m D+
20 km
900 m+
20 Km – 900m D+
10 km
400 m+
10 Km – 400m D+
Visit the organization's website for the most recent information.