Be aware of the altitude!
Cusco was the capital of the Inca Empire and is located 3,399 meters above the sea level. It is recommended to stay there for a couple of days as the altitude sickness may occur. As a matter of fact, there is no cure to this sickness other than descending to a lower altitude. However, if you want to see Machu Picchu, you need to pass through Cusco. No worries, there are so many beautiful things in the city and around it, that you will feel dizzy anyway.
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