The Pyramid of the Moon is the second largest pyramid located in modern-day San Juan Teotihuacán, Mexico. The structure existed prior to 200 AD. A slope before the staircase gives access to the Avenue of the Dead. A platform atop the pyramid was used probably for conducting ceremonies in honour of the Great Goddess of Teotihuacan. Archaeologists say that the Teotihuacans were upgrading the structures often. They were not happy with their architectural feats for very long. The pyramids underwent at least six facelifts over a period of several hundred years, and each new addition was larger and built over the previous structure.