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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

Saturday Feb 14

Saint Valentin Forever Run

Saint-Germain-en-Laye

The Saint Valentin Forever Run will take place in Saint-Germain-en-Laye on Saturday 14 February 2026. You can run between 5 and 25 kilometers.

UTMB Index

Sunday Feb 15

Cross de la Sablière

...

The Cross de la Sablière will take place in Viroflay on Sunday 15 February 2026. You can run between 6 and 11 kilometers.

Sunday Feb 15

Semi Marathon de Bullion

Bullion

The Semi Marathon de Bullion will take place in Bullion on Sunday 15 February 2026.

Sunday Mar 8

Trail des Aigles

Gouvieux

9 km

16 km

The Trail des Aigles will take place in Gouvieux on Sunday 8 March 2026. You can run between 9 and 16 kilometers.