Final answer:
The Templo Mayor was at the center of Tenochtitlán, serving both spiritual and physical functions. Aztecs and visitors conducted religious ceremonies and sacrifices there.
Step-by-step explanation:
The center of the city, both spiritually and physically, was dominated by the Templo Mayor, which consisted of two temples on top of a pyramidal base dedicated to the gods Tlaloc and Huitzilopochtli. This area was the heart of the Aztec capital known as Tenochtitlán, which is today's Mexico City.
The Templo Mayor hosted the most significant Aztec rituals, religious ceremonies, and the naming of their leaders. It underwent seven building phases, reflecting the empire's expansion and increasing the temple's grandeur and size with each new phase. Aztecs and visitors came to the Templo Mayor for participation in religious activities, offerings, and to witness rituals, including human sacrifices that were made to appease the gods and maintain cosmic order.