Machu Picchu (2,430 m) is the 15th-century Inca citadel built on a ridge above the Urubamba River. Visits follow timed circuits with daily limits, so tickets should be booked weeks ahead. Most travelers arrive by train from Ollantaytambo to Aguas Calientes, or on foot via the Inca Trail, Salkantay or Lares.
Best time: April–October. Getting there: train + 25-min bus, or a multi-day trek.
