Teotihuacan, located in the modern day State of Mexico, was originally an empty site prior to the first century AD, but the eruption of the Xitle volcano at the end of century caused a massive migration of indigenous groups to the valley, since their ancient cities were destroyed. The migrant people who settled in the valley from the time frame of 1-150 AD, commonly referred to as the Tzacualli phase, began to build the three main constructs of Teotihuacan. These constructs were the Pyramids of the Sun and Moon and the Temple of the Feathered Serpent. The most imposing structure at the site of Teotihuacan is the Pyramid of the Sun. It is the third largest pyramid in the world at 65 meters in height, 22 meters taller than its twin construction the Pyramid of the Moon. These twin contsructs are built on the same level. It was the first main structure to be made in Teotihuacan and is responsible for the city’s growth into a trade hub and place of religious significance, similar to Cozumel.
The first of these massive edifices was the Pyramid of the Sun. The pyramid was built with the idea of three concepts: to be the physical embodiment of Tonacatepetl, temple of Tlaloc, and the religious significance of the cave beneath the structure. The concept of the Tonacatepetl, which means “mountain of significance,” comes from the Mesoamerican belief in creating massive mountain-like structures to appease the rain god and, as a result, produce rain. Tlaloc, who is the chief god of the sky and fertility, is the god to which the pyramid was constructed. The Sun pyramid is meant to honor him, while the Pyramid of the Moon is built for his wife Chalchiuhtlicue the goddess of flowing water. The cave under the pyramid is seen by the native people as a way to the “center of the universe.” Since caves hold a variety of supernatural meanings to the indigenous groups, the cave underneath the temple has a great amount of religious significance (Linda Manzanilla, The Oxford Encyclopedia of Mesoamerican Cultures, Teotihuacan).
The cave located under the Pyramid of the Sun was uncovered in 1971 by a group of archeologists. The cavern was naturally formed around a million years ago due to the flow of lava. The cave was found with a staircase and was a formerly decorated site of religious sacrifice, until the arrival of grave robbers. Since the corpses of victims are no longer available for dating, there are no accurate estimates at the earliest time of ritual sacrifice. The cave is a symbol to the native people of Mesoamerica as a representation of creation. In some stories, the god Quetzalcoatl retrieves the bones of man and the variations of corn from a cavern in the earth. As stated by Doris Heyden in American Antiquity, native groups believed that the god of fire, Xiuhtecuhtli, is housed in the center of the earth in a “turquoise enclosure” (Doris Heyden, American Antiquity, 131-141). In a much more general sense, the caves are also related to the homes of ancestors, a place of revival or origin, oracles, and the supernatural.
Though the structures such as the Pyramid of the Moon and the Temple of the Feathered Serpent are certainly significant, the Pyramid of the Sun and its natural cavern helped to make the city of Teotihuacan a place of religious significance. This spirituality caused the migration of the people to the site, and made the city one of the most important sites in Mesoamerica in terms of trade and pilgrimage.