Hey fellow trekkers, I've been guiding groups through the Inca Trail for years and still see people getting altitude sickness. We're at high risk of AMS even in Peru's lower elevations, so it's crucial to acclimatize properly before attempting La Ruta de los Incas. My top tip is to spend a day or two exploring Cuzco and then take a day hike up to the Sacred Valley before tackling the full trail
