Cusco was the Spanish city founded on the site of the Inca capital in 1534.
Cusco had been the political, religious, and administrative center of Tawantinsuyu, the Inca Empire. Spanish forces entered the city in November 1533 after capturing Atahualpa, and Francisco Pizarro formally reestablished it as a Spanish city on 23 March 1534.
The conquerors did not build on an empty site. They reused Inca walls, foundations, streets, and building materials, placing churches and colonial structures over or beside imperial monuments. This is why Cusco still displays a striking combination of finely fitted Inca masonry and Spanish colonial architecture.
Quito, Lima, and Arequipa are important colonial-era cities, but they do not fit the clue. Lima became the principal Spanish administrative capital of Peru, while Cusco remained the symbolic and historic heart of the former Inca realm.