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Les 40 Bosses

Name: Les 40 Bosses
Start: 2026-12-05
End: 2026-12-06
Location: Saint-Leu-la-Forêt

Saint-Leu-la-Forêt, France • 5-6 Dec 2026

The Les 40 Bosses will take place in Saint-Leu-la-Forêt from Saturday 5 December 2026 to Sunday 6 December 2026. Visit the organization's website for the most recent information.

France Val-d'Oise Île-de-France Saint-Leu-la-Forêt

Race information

Website

UTMB 20K UTMB 50K UTMB 100K UTMB 100M

Les 40 Bosses - 75 Km

Les 40 Bosses - 120 Km

Les 40 Bosses - 20km

Les 40 Bosses - 45km

Visit the organization's website for the most recent information.

Trail runs nearby

Fri - Sat Jan 16-17

Yerres Trail by Night

Yerres

12 km

22 km

The Yerres Trail by Night will take place in Yerres from Friday 16 January 2026 to Saturday 17 January 2026. You can run between 12 and 22 kilometers.

Sunday Jan 25

Trail des Marcassins - Saint-Brice-sous-Forêt

Saint-Brice-sous-Forêt

15 km

30 km

The Trail des Marcassins - Saint-Brice-sous-Forêt will take place in Saint-Brice-sous-Forêt on Sunday 25 January 2026. You can run between 15 and 30 kilometers.

Sat - Sun Jan-Feb 31-1

Maxicross Bouffémont

...

The Maxicross Bouffémont will take place in Bouffémont from Saturday 31 January 2026 to Sunday 1 February 2026. You can run between 10 and 60 kilometers.

UTMB Index

Sunday Feb 1

Diodurun

Saint-Rémy-l'Honoré

7 km

The Diodurun will take place in Saint-Rémy-l'Honoré on Sunday 1 February 2026. You can run 7 kilometers.