From Menton, on the edge of the Mediterranean, to Heiligenblut, at the foot of the Grossglockner in Austria, the author invites us to crisscross the Alps for more than 1000 kilometers on skis - or on our backs when necessary. Philippe Ertlen divided the route into 61 stages, enriched with 50 variants. It also proposes a division of all these stages into eleven raids of approximately one week, which can be carried out in one or more times. Each stage is the subject of a detailed description accompanied by a sketch and valuable information on accommodation and public transport. Anecdotes from the author and inserts of a historical, geographical or faunal nature help to make this guide essential.