Cusco or Cuzco (Latin American Spanish: [ˈkusko]; Quechua: Qosqo or Qusqu, both pronounced [ˈqosqɔ]) is a city in southeastern Peru, near the Sacred Valley of the Andes mountain range and the Huatanay river. It is the capital of the eponymous province and department.

The city was the capital of the Inca Empire until the 16th-century Spanish conquest. In 1983, Cusco was declared a World Heritage Site by UNESCO with the title "City of Cusco". It has become a major tourist destination, hosting over 2 million visitors a year and providing passage to numerous Incan ruins, such as Machu Picchu, one of the Seven modern wonders of the world and many others. The Constitution of Peru (1993) designates the city as the Historical Capital of Peru.

Cusco is the seventh-most populous city in Peru; in 2017, it had a population of 428,450. It is also the largest city in the Peruvian Andes and the region is the seventh-most populous metropolitan area of Peru. Its elevation is around 3,400 m (11,200 ft). The largest district in the city is the Cusco District, which has a population of 114,630 in 2017, making about one fourth of the cities total population.