Paths (pedestrians) were the only way to communicate within the gigantic empire of the Incas, from southern Colombia to Chile. Among all these routes, the Inca Trail was the main and heavily used route between the imperial capital, Cusco, and the major spiritual and cultural site of Machu Picchu. There are therefore many buildings between these two important centres: today, following in the footsteps of the Inca messengers, we cross a very large number of remains, ruins, dwellings and various constructions installed to improve communication as much as possible on either side of the high snow-covered peaks of the Andes.