Pierre Lesueur, born in Clichy (France) on January 23, 1928, is one of the representatives of the famous group of Parisian climbers who marked the history of French mountaineering in the 1950s, with in particular the first of the face south of Aconcagua. During the week, while Robert Paragot repairs typewriters at Social Security, Pierre Lesueur cuts metal parts at the factory. On weekends, they meet up with the whole gang in Fontainebleau to climb the rocks or, better yet, hitchhike to Chamonix, with the heavy pitons made by Lesueur in their backpacks. “I was a fitter because my father was a fitter, I couldn't be anything else. I worked at night. I was watching stuff and didn't have much to do, so I was doing pitons because we didn't have a lot of money to buy them. This anecdote, told by Pierre Lesueur, is perhaps the one that best sums up the era and the state of mind that reigned, in the early 1950s, within this formidable team of Parisian climbers led by Robert Paragot. , Lucien Bérardini, Edmond Denis, Adrien Dagory and the Lesueur brothers. In 1950, Paragot and Lesueur climbed the north face of the Petit Dru by the route opened in 1935 by Pierre Allain, the master, trained like them at the school of bleausarde and already nicknamed "the Old", as if to signify the handover. With yet another good anecdote: “At Dru, I had old shoes and the sole opened in the Lambert crack. It had to be fixed with a wire. They are still fabulous stories! It was a good time ! » In the summer of 1952, ambitions were on the rise and Lesueur first took on the Walker on the north face of the Grandes Jorasses with his brother Henri, Edmond Denis and still Robert Paragot. Then the brothers go to Les Drus, on the Grand this time. They need two bivouacs to open the Lesueur route on the left of the north face. A few days earlier, Magnone, Bérardini, Dagory, and Lainé had successfully completed the first of the formidable west face. Les Bleausards are at the top of their game! Going on an expedition to the end of the world is the logical continuation of alpine adventures. In December 1953, the band of Parisian proletarians flew to Buenos Aires with the south face of Aconcagua in their sights. Here again, the trip is organized thanks to the funds of each other. We don’t even take a return ticket: “no need to waste money” wrote Paragot in Vingt ans de cordée (Flammarion, 1974). On February 25, after five bivouacs, Pierre Lesueur was at the top with Edmond Denis, Guy Poulet, Adrien Dagory, Lucien Berardini and Robert Paragot. The end of the ascent was a nightmare. After the last bivouac, the men are exhausted and the extremities are frozen. All except Paragot will be seriously amputated... For Pierre Lesueur, who wanted to become a guide, it will be the end of his career at high altitude. Pierre Lesueur, nicknamed "Lafleur" by his rope companions, will die in 2021 at the age of 94 in Étampes (France).