Trail Blanc Mouthe is a winter night trail race held in Mouthe, a village in the Doubs department of eastern France, situated high in the Jura massif at approximately 930 meters. The location imbues the race with its character: Mouthe is frequently referred to as the French North Pole, and the lowest temperature ever recorded in France, -36.7°C, was registered there. Participants can select 10 km or 20 km courses, with an additional Trail XS option extending to about 24 km and featuring 650 meters of elevation gain.
The race crosses snowy forests under the cover of darkness and the sharp January cold, making a headlamp a mandatory piece of equipment rather than an optional item. It serves as an early-season event for runners seeking a challenge more demanding than a road race and colder than a typical trail run. The organizers embrace the playful aspect of the name: while no mammoth is present, participants are encouraged to wear moumoute, which translates to fluffy or furry attire, a fitting choice for the frozen environment over standard race singlets.