Monte San Lorenzo is the second-highest mountain in Patagonia, 3,706 metres on the border of Argentina and Chile, and one of the least climbed in the whole range. The weather is the reason. Fog can shut the summit within minutes of a clear sky, and wind and snow turn back most parties who try it. Fitz Roy, four hundred kilometres south, draws crowds to similar granite; this one is largely left alone. Three glaciers pour off it, two into Argentina and one into Chile, and each country has its own name for the mountain. Argentina calls it San Lorenzo, for the saint. Chile calls it Cochrane, after the British admiral who commanded the Chilean navy in the war of independence, a name the town and the lake at its foot carry too.
Most people who come this far never intend to climb it. Trails take you through lenga and ñire beech forest and along cold glacial streams toward the foot of the mountain, and the loudest thing out there is the wind. You can walk for hours and cross nobody. Those woods hold the huemul, an endangered Andean deer down to about 1,500 animals in the wild and seen here more often than almost anywhere, with condors working the ridges above and guanacos out on the steppe. In late spring the valleys below the snowline green up and wildflowers open across the steppe, the gentlest stretch of the year between the retreating snow and the summer wind. The long approach ends at the De Agostini base camp under the hanging glaciers, where you wait out black, freezing hours before sunrise. Then the sun clears the steppe and strikes the high face first, so the peak is lit while the valleys around you are still in shadow. The camp is named for the man who reached the top first. Alberto María de Agostini was a Salesian priest who had spent decades mapping and photographing Patagonia, and it took him three summers to find a way up this mountain; he was sixty when he stood on it, in December 1943.