Eighty-three square kilometres of city 40 km northeast of Mexico City, holding somewhere around 100,000 people at its height about AD 400 to 500, and nobody knows for certain who built it. Candidates include Nahua, Otomi and Totonac peoples, and the evidence points to a multi-ethnic place drawing migrants from across Mesoamerica, particularly Oaxaca and the Gulf Coast. The Aztecs found it already abandoned and gave it the name we use, which means birthplace of the gods; what its own people called it is gone. From 2009 excavation under the Temple of the Feathered Serpent reached a chamber 17 metres down holding a miniature mountain landscape with tiny pools of liquid mercury standing in for lakes. UNESCO World Heritage since 1987.
State of Mexico, Mexico
See it on the map
