Teotihuacan is an ancient Mesoamerican city located in a sub valley of the Valley of Mexico, which is located in the State of Mexico, 40 kilometers (25 mi) northeast of modern-day Mexico City. Teotihuacan is known today as the site of many of the most architecturally significant Mesoamerican pyramids built in the pre-Columbian Americas.

Teotihuacan began as a religious center in the Mexican Highlands around the first century AD. It became the largest and most populated center in the pre-Columbian Americas. Teotihuacan was home to multi-floor apartment compounds built to accommodate the large population. The term Teotihuacan (or Teotihuacano) is also used for the whole civilization and cultural complex associated with the site.

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