This mythical descent is the off-piste ride of a lifetime. A veritable obstacle course of a route, La Vallée Blanche takes four to five hours, leading from Aiguille du Midi over the crevasse-riddled Mer de Glace glacier and back through forest to Chamonix, covering 2800m of jaw-dropping vertical. Because of the obvious risks, it must only be tackled with a guide (guides can take a maximum of eight people in a group – add an extra €16 per additional person to the price above). Snowboarders require an even better level than skiers. Snow coverage is generally best in February and March.