Teotihuacan was located in the highlands of present day Central Mexico. Around 600 BC people lived there about 100,000 and 200,000, making it one of the ancient world’s largest cities with an urban covering some twenty square kilometers. Settlement began about 200 B.C. The earliest building at Teotihuacan dated about 200 B.C. The largest pyramid, Pyramids of the Sun was completed by 100 CE.
The early history of Teotihuacan is mysterious, and the origin of its founder is debated. For years, archeologists believed that the Toltec built Teotihuacan. However, since Toltec civilization flourished centuries after Teotihuacan, they cannot be understood as the city of Teotihuacan founders.
Other scholars believed that the Totonac people as the founders of Teotihuacan. There is evidence that at least some of people lived in Teotihuacan, came from areas influenced by Teotihuacano civilization, including Mixtec, Zapotec and Maya. Olmec people influenced the structure and culture of Teotihuacan.
The city of Teotihuacan was center of industry, pottery, jewelers and craftsmen’s. Teotihuacan also known for producing a great number of obsidian artifacts. The religion of Teotihuacan is similar to those of other Mesoamerican cultures. Many of the same gods were worshiped, including the Feathered Serphent and the Rain God. Teotihuacan was a major religious center, and the priests probably had a great deal of political power. Teotihuacanos also practiced human sacrifice.
The city of Teotihuacan broad central avenue, called Avenue of the Dead, is flanked by impressive ceremonial architecture, including the immense Pyramid of the Sun and the Pyramid of the Moon. Along the Avenue of the Dead are many smaller talud-tablero platforms. Further down the Avenue of the Dead is the area known as the Citadel, containing the ruined Temple of the Feathered Serpent. This area was a large plaza surrounded by temples that formed the religious and political center of the city. The name "Citadel" was given to it by the Spanish, who believed it was a fort. Most of the common people lived in large apartment buildings spread across the city. Many of the buildings contained workshops that produced pottery and other goods.
Sometime during the mid-seventh century, certain sectors of the city, particularly around the Pyramids of the Sun and Moon, were repeatedly burned and sacked, probably by Toltecs. The city never recovered from these attacks