Seven Wonders of Ancient North America, Michael Woods and Mary B. Woods, Twenty-First Century Books, Minneapolis, MN, 2009.
Teotihuacan is an ancient Aztec city about thirty miles north of Mexico City. It includes a Pyramid of the Sun, Pyramid of the Moon and Avenue of Death. Teotihuacan was first settled in BC 100 and by 100 AD was the largest city in the New World with over 125,000 residents. People are not sure where these people have gone, but the Aztecs claimed them as ancestors. It is believed to have been burned and sacked in 550 AD and totally uninhabited a couple hundred years after this. It could well have been a place where people from many different groups met. The influence to Teotihuacan is very wide, with it obsidian products being traded extensively.