11 Days on the “Great Crossing of the Massif Central” (GTMC)

In late September 2025, I spent 11 riding days riding the GTMC in France. What follows is a trip report along with some things I wish I had known before setting out on this adventure.

The Trail

The GTMC is a long-distance mountain bike route that traverses the entire Massif Central, a highland region in south-central France made up of mountains and plateaus. My initial plan was to ride the mountain bike line from Millau to Clermont-Ferrand. After just one day, I realized it was not suitable for loaded touring. I switched to the gravel line, which turned out to be challenging enough.

The route is designed to be ridden from north to south, ending at the Mediterranean. For practical reasons, I rode it in reverse, heading north. This meant crossing paths with bikepackers every couple of days but never finding companions to ride with. It was my first solo bikepacking experience.

The Bike

I brought the same bike I used on the southern half of the GDMBR (Steamboat Springs to Mexico): my trusty Surly Ogre with Moloko alt-bars and a B17 saddle, but upgraded with stronger rims and wide mountain bike tires. That choice paid off. Calling the route a gravel line is misleading. Almost every day, I hit sections that would have been miserable on tires narrower than 2.4”. Riders on loaded gravel bikes looked like they were suffering.

A Brutal Start

The departure from Millau on the MTB line was punishing: steep, technical terrain, relentless climbing. Fun maybe on a light mountain bike or with e-assist, but not on a loaded rigid bike. I dropped my tires to 15 psi just to keep moving. That night, I switched to the gravel line.

But the suffering was not over. On day three, I faced a 12 km (7.5 mi) climb at 12%, with long stretches of loose rock. I love climbing and fondly remember ascending Mt. Lemmon in Arizona on a road bike, but this was the hardest climb of my life. By the end of the day, after just 50 km (31 mi), I collapsed into a campsite. A fellow camper warned me that more such climbs awaited since I was riding the route backwards. Luckily, he was wrong. I still had to push my bike nearly every day, but nothing as extreme as that third-day climb.

Weather Shift

The first few days were perfect: sunny and 25°C (77°F). Then, as I descended Mt. Aigoual into the Tarn Gorge, l was warned of a major storm. I took shelter in Florac, spending the day in a hotel drying out and planning escape routes. That decision paid off. Many riders were caught outside during the “Sunday storm.”

After Florac, the weather turned. For four days I rode through drizzle, fog, and cold, with daytime highs of just 4°C (39°F). I stayed functional thanks to warm gear, but nothing ever dried fully. Twice I took refuge in lodgings to warm up and dry out, including one Camino de Santiago pilgrims’ hostel. I am not religious, but for one night I played the part.

Settling In

In the mist, woolly cows loomed like ghosts, and I slogged through mud and puddles. But I began to get ahead of schedule. I had planned for about 70 km (43 mi) per day to reach Clermont-Ferrand before my flight, but now only needed about 55 km (34 mi). For the first time, I felt sure I would make it.

Thankfully, the skies cleared for my final days, just in time to see the Chaîne des Puys, a chain of about 80 volcanic cones.

The Finish

I rolled into Clermont-Ferrand proud and relieved. It was proof to myself that I could handle a long solo bikepacking trip.

Over 11 riding days, I covered 722 km (449 mi) and climbed 11,436 m (37,519 ft). The route was a mix of paved roads, good gravel, and rough tracks, with short, punchy climbs. Food and water were easy to find: a grocery store every other day, a village fountain almost daily. Only once did I filter water, after that brutal third-day climb drained all three liters.

Compared to the GDMBR, the GTMC was physically harder thanks to steep grades and rough surfaces, but logistically simpler. With more planning, I could have stayed indoors every night, though lodgings were often full even this late in the season.

Food & Encounters

My diet consisted largely of pains au chocolat, croissants, and dried sausage. A small baguette fits perfectly in my frame bag. I occasionally indulged in good beer and wine, taking advantage of the local terroir.

Along the way, I met unflappable farmers, surprised hunters, unprepared cyclists (misled by the word “gravel”), and kind but rowdy drunks. Every encounter was welcome on an otherwise sometimes lonely ride.

I am now in a train back to Bordeaux, resting my legs and happy to answer any questions about my GTMC experience or my gear.