<P> At its zenith, perhaps in the first half of the 1st millennium AD, Teotihuacan was the largest city in the pre-Columbian Americas, with a population estimated at 125,000 or more, making it at least the sixth largest city in the world during its epoch . </P> <P> Apart from the pyramids, Teotihuacan is also anthropologically significant for its complex, multi-family residential compounds, the Avenue of the Dead and the small portion of its vibrant murals that have been exceptionally well - preserved . Additionally, Teotihuacan exported fine obsidian tools that garnered high prestige and widespread usage throughout Mesoamerica . </P> <P> The city is thought to have been established around 100 BC, with major monuments continuously under construction until about 250 AD . The city may have lasted until sometime between the 7th and 8th centuries AD, but its major monuments were sacked and systematically burned around 550 AD . </P> <P> Teotihuacan began as a new religious centre in the Mexican Highlands around the first century AD . This city came to be the largest and most populated centre in the pre-Columbian Americas . Teotihuacan was even home to multi-floor apartment compounds built to accommodate this large population . The term Teotihuacan (or Teotihuacano) is also used for the whole civilization and cultural complex associated with the site . </P>

When did the teotihuacan civilization start and end
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