Zona Arqueológica de Teotihuacán, San Juan Teotihuacán, Mexico

This city lasted from somewhere around the year 1 to the year 500. Somewhere as I child I learned that ancient civilizations tended to last about 500 years. I threw this idea into a search engine and found a very lengthy blog post on the site Owlcation tackling this very question. A review of 74 civilizations found an average length of 349 years with a range of 14 to 1,100. Plenty of commenters quibbled with the definitions of “civilizations”, of course.