Le Bourg-d'Oisans

From Bourg-d'Oisans the pilgrimage is obvious: twenty-one numbered lacets to Alpe d'Huez. The loop that makes the day is what follows — the wild, quiet Col de Sarenne at 1,999 m and a technical return past Lac du Chambon.

Two Tour de France cols linked from Bourg-d'Oisans in one loop: up the Combe d'Olle to the iron cross at 2,067 m, a short spur to the Glandon, then thirty-seven kilometres back past turquoise reservoirs — 79.1 km and 1,908 m of climbing that never quite finish when the descent begins.