The Templo Mayor was the main temple of the Aztecs, also known as Mexica, in their capital city of Tenochtitlan, which is now Mexico City.
Back in 1978, electrical workers laying underground cables accidentally discovered this high temple just two blocks off the Zocalo, the main plaza of the Mexico City. Since then, various excavations around the area, many under modern construction, and research have increased the understanding of daily life, religion and government of the Aztec peoples of pre-colonial Mexico.
The main shrine of the temple was demolished by the Spaniards and upon it, they built the Metropolitan Cathedral. But apparently, there were at least six earlier versions of the temple lay underneath, the result of each successive ruler building his own temple on top of the previous one.
These layers of buildings are giving archaeologists (and the public) unprecedented look at Aztec society. A museum housing artifacts of Aztec antiquity is built nearby.