01
Acclimatise before you go.
Don't fly into Cusco (3,400m) and go straight to the citadel - you'll feel rough at altitude. Spend 2-3 nights in the Sacred Valley first (Urubamba or Ollantaytambo, 2,800m, much easier on the body). The citadel itself is lower (2,430m) but the bus to it leaves from Aguas Calientes pre-dawn.


