A one stage, free-style, day and night foot race around a looped circuit on varied terrain in the Gulf of Morbihan that includes a ten minute mid-race boat crossing from Locmariaquer to Port-Navalo. Maximum completion time is set at 42 hours (including all breaks). Runners are required to clock in within the required time limits at various check points (§3 of rules). the ship time will be deducted from final time.
This race is limited to 1300 trailers.