Rather calm until Lavelanet, the journey into the Pyrenees rapidly becomes a roller-coaster ride as of Montségur: the citadel of vertigo and its rough climbs, then the Col de la Croix des Morts and Col de Saint-Louis that the riders will reach by riding on the spectacular Viaduc de l'Escargot, will sharpen the appetite of the hungriest climbers.
