Qorikancha, which means golden temple in Quechua, is located right in the city of Cusco. It was the most important temple in the Incan Empire and defined opulence. Floors and walls were made of gold, for example.
When the Spanish arrived, they demolished the temple and used the foundation to make The Church of Santo Domingo. This was quite common of the Spanish, actually, and in Cusco you can see many examples of stone foundations from the Incas supporting European-style buildings.
The Incans were master masons and you can see in the pictures below that the stones fit together perfectly without mortar. This makes them highly resistant to earthquakes, which are common in Peru.
The site is on a hill and you can get great views of Cusco.
Qorikancha was the first of many Incan and pre-Incan sites I visited in Cusco. It definitely whet my appetite for more despite having little to say about it.