Largest city in the world in pre-Columbian times

Teotihuacan near the site of present day Mexico City (about 25 miles away) is considered by far and away to be the largest city in Mesoamerica during the pre-Columbian period. It ranked in population with the biggest cities of either Europe or Asia. Noted for its spectacular pyramids, the city was begun circa 200 BC and seems to have waned in its political power around 650—in fact some historians and archaeologists contend that at one time, it was the largest city in the world. At its height in approximately 450 AD, the population had soared to more than 150,000 people and possibly as many as 250,000. Interestingly enough, scholars are not absolutely certain who built the city. Ethnically, it was a diverse city with separate areas where the Otomi, Zapotec, Mixtec, Maya and Nahua peoples lived—a harbinger of the ethnic neighborhood of our own time. Although the Aztecs later claimed that their ancestors had founded the city, archaeologists today dispute that. Thses neighborhoods might be considered the first ethnic neighborhoods in a large city.