This great crossing of the Pyrenees, between the Atlantic and the Mediterranean, carried out alone on the legendary GR10 in 67 days, is much more than a long hike of 900 km; it is an immersion in the heart of "Pyreneanism". A deeply human film that elevates us to high-altitude lakes and also leads us to locals who tell us about their lives, their languages and their traditions. They are storytellers, Pyrenees National Park guides, mountain guides, historians, refuge keepers or shepherds. We discover this Pyrenees range rich in exceptional fauna and flora: marmots, chamois, vultures... From bivouacs to refuges, we walk on the GR10 to discover this mountain in all its biodiversity and splendor. A favorite film which required three years of filming.