In his letters, Cortes tries not to miss any vital information and tries to report all the details about the city. His descriptions make his writing a primary source. Cortes chose certain topics which makes his writing audience-oriented. He also mentions the knowledge about the geology of the area because it was the indicator of life and death for early conquerors. Additionally, Cortes describes the beauty of the city, its wealth, rare objects, including the barbarity and ritual abuse of Aztec religion.