Why was machu picchu built and what was its function?

Machu Picchu was built in the 15th century during the reign of the Inca emperor Pachacuti as a royal estate and religious site. Its functions included serving as a ceremonial center, a royal retreat, and an agricultural hub, with extensive terraces for farming. The site's strategic location also provided a defensive advantage and facilitated trade and communication within the Inca Empire. Today, it remains a symbol of Inca engineering and culture.