A 170K ultra-trail between Mont-Saint-Michel and Granville under consideration for 2027

Following the announcement of the Bay Marathon's return, another major project is taking shape around Mont-Saint-Michel. Event agency Wima Sport, based in Avranches and already behind the Trail de Jullouville and the Granville triathlon, is currently working on an ultra-trail linking the Norman landmark with the seaside resort of Granville. Nothing is official yet, however: not the race name, entry fees or cutoffs. But the outline of the project is beginning to emerge, and it could surprise seasoned ultra-runners.

A course that goes against the ultra norm

On paper, the project's headline distance is impressive: 170 kilometres. But its elevation profile is what really stands out. Around 1,500 metres of elevation gain are planned over the full course, averaging fewer than 10 metres of climbing per kilometre. That's negligible compared with benchmarks such as UTMB, Tor des Géants and Diagonale des Fous. The format would be closer to that of l’Ultra Marin (175 km, 1,430 metres of elevation gain), another race held in a bay, this time the Gulf of Morbihan.

© ASO

On a course this runnable, there would be no long climbs or technical sections to rein in the pace. The main challenge would be sustaining a long effort with few genuine breaks. That demands a different skill set from mountain ultras, along with the ability to hold a strong pace for hours on end. For trail runners used to alternating running and hiking on steep slopes, this kind of terrain, where opportunities to recover are few and far between, could prove especially punishing.

That is the project's defining feature: offering an ultra-trail distance in a setting where the real difficulty would come from the miles rather than the climbing.

From Mont-Saint-Michel to Granville via Avranches and Villedieu-les-Poêles

According to the first drafts, the 170K course would start at Mont-Saint-Michel and pass through Avranches, Villedieu-les-Poêles, La Haye-Pesnel, Sartilly-Baie-Bocage, Jullouville and Saint-Pair-sur-Mer before reaching the finish in Granville.

The project would not be limited to a single distance. Three other formats are under consideration: 100 km, 50 km and 20 km, with starts planned from Avranches and Jullouville, also heading towards Granville. That would create options for a wide range of runners, from newcomers drawn to their first long-distance challenge to experienced ultra specialists looking for something out of the ordinary.

UTMB ecosystem integration under discussion

Another factor that could matter to both organisers and runners is the possibility of joining the UTMB ecosystem, with points awarded towards applications for races on the circuit. No specific details have been announced at this stage, however, and the project is still being developed.

Finding a date in an already busy local calendar

Wima Sport is considering staging the event in mid-October 2027. The date would then have to be fitted into an already crowded regional calendar. Mont-Saint-Michel Bay hosts several sporting events at that time of year, notably the Bayman, the triathlon held in the bay. It is an issue the agency will have to address before making anything official.

Beyond this particular project, the announcement confirms a broader trend: year after year, Mont-Saint-Michel is becoming an increasingly sought-after destination for running events. The Norman landmark has a major asset, too: a UNESCO World Heritage setting known far beyond France's borders.

With the announced return of the Mont Saint Michel Marathon and this unusually designed ultra-trail project, the bay could well become one of France's destinations to watch for road runners and trail enthusiasts by 2027.