Final answer:
The richest complex in the city of Cusco was the Coricancha. It was an important religious site for the Inka civilization and was covered in sheets of gold. The lower walls of the complex were made of perfectly fitted stone without mortar.
Step-by-step explanation:
The richest complex in the city of Cusco was the Coricancha. It was an important religious site for the Inka civilization and was covered in sheets of gold. The Spanish built the Convent of Santo Domingo on top of the original Inkan Qorikancha Temple, transforming it into a church. The lower walls of the complex were made of perfectly fitted stone without mortar, showcasing the Inka's skill in stone masonry.