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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 - 120 Km

Les 40 Bosses - 20km

Les 40 Bosses - 45km

Les 40 Bosses - 75 Km

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

Trail runs nearby

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.

Saturday Feb 7

La Trifouillette Blanche

Igny

10 km

20 km

The La Trifouillette Blanche will take place in Igny on Saturday 7 February 2026. You can run between 10 and 20 kilometers.