Why the incas leave Machu Picchu?

The Incas likely abandoned Machu Picchu in the 16th century due to a combination of factors, including the Spanish conquest, civil war, and the spread of diseases like smallpox. The site, which served as a royal estate and religious center, became less sustainable as the Inca Empire deteriorated. Additionally, its remote location may have made it difficult to maintain and defend. Ultimately, the decline of the Inca civilization led to the abandonment of this iconic site.