Running the Mont Blanc ultra, the world’s most famous trail race

With its dizzying ridges and stunning views, Mont Blanc is home to some of the world’s best trail running

I’ve been running uphill for over an hour, scaling this narrow mountain trail, when we pass through some trees. This must be the top, I’m thinking, hopefully, as we crest the pass. But alas, rising up on the other side are more hulking mountains and snaking up through the middle of them, like a line of ants, are the tiny dots of the runners ahead of us.

“Putain,” swears the French runner behind me. I know exactly how he feels. The 170km Ultra Trail du Mont Blanc is the most famous trail race in the world. In the fast-growing sport of Mountain Ultra Trail (MUT) running, it’s the big one, the sport’s Super Bowl. For a week at the end of August each year, the town of Chamonix in the French Alps is completely taken over by ultra runners and their supporters. Any unsuspecting visitors arriving in the area would be left baffled by this strange world of short shorts and little backpacks and super-fit people that they’d wandered into.