Pyramid of the Sun in Teotihuacan, Mexico

A very large stone pyramid rises from a grass field. The pyramid is composed of several different levels, with stairs leading from level to level. The Pyramid of the Sun is the largest structure in Teotihuacan, and the second largest in Mesoamerica. It is also the third largest pyramid in the world. The original purpose of the Pyramid of the Sun is unknown, though archaeologists believe it originally had an altar on top of the Pyramid. Therefore, it most likely was built to honor a deity. Unfortunately, looting over the years has reduced the material available for study.Teotihuacan is the name of a Mesoamerican indigenous civilization and its grandest city, once the largest city in Mexico. The Teotihuacan people predated the Maya by over five hundred years, and the Aztec by more than a thousand years. The civilization of Teotihuacan reached its height in the 1st century CE (AD) when the huge pyramid to the sun was built. The estimated population of the city at its largest varies from 150,000 to 250,000. Artisans of the city are known for the sweeping grandeur of the buildings they left behind, and numerous artifacts made from obsidian, a black volcanic rock indigenous to the region. The reason for the decline of the city and its civilization after 450 CE (AD) is unknown. Some archaeologists hypothesize that climate change and severe droughts led to internal unrest that may have caused the destruction of the city. Today, Teotihuacan is a popular tourist destination replete with museums and ongoing archaeological investigation.