Col de Sarenne is an Hors Catégorie (beyond-category) climb in Alps — 12.89km at 7.3% average gradient, cresting at 1,999m. It's the last major climb of Stage 20 of Tour de France 2026 (Le Bourg d'Oisans → Alpe d'Huez, 170.9km), cresting 14.4km from the finish — often the launchpad for the day's decisive move. Set your groupset — Shimano, SRAM, Campagnolo or a custom setup — and see exactly which gears get you up it, kilometre by kilometre.
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