Imagine you begin pedaling from the start of Stage 12 of this year’s Tour de France. Your very first task would be to bike approximately 20.6 miles (33.2 km) up to the peak of Col du Galibier in the French Alps while gaining around 4,281 feet (1,305 m) of elevation. But this is only the first of three big climbs in your day. Next you face the peak of Col de la Croix de Fer and then end the 102.6-mile (165.1-km) stage by taking on the famous Alpe d'Huez climb with its 21 serpentine turns.
