Which ancient city is famous for the Inca citadel built high in the Andes?

Machu Picchu is the ancient Inca city famous for its high-Andes citadel.

Machu Picchu was built in the fifteenth century during the reign of the Inca ruler Pachacuti. It stands at about 2,430 metres above sea level in Peru, between the Andes and the Amazon basin, and contains terraces, plazas, temples, and finely fitted stone buildings.

The site was probably a royal estate or sacred retreat rather than the ordinary capital of the Inca Empire. Its builders used sophisticated masonry and agricultural terraces adapted to steep mountain slopes.

The outside world learned about Machu Picchu through Hiram Bingham’s 1911 expedition, although local residents already knew of the ruins. It was never the empire’s capital: Cusco served that role. Machu Picchu became a UNESCO World Heritage Site in 1983.