This thing was found by mistake!

On February 21, 1978, electrical workers were putting down lines on a busy street corner in Mexico city when they discovered a 20 ton stone bas-relief of the Aztec night goddess, Coyolxauqui. It is believed to have been sculpted in the early fifteenth century and buried prior to the destruction o the Aztec civilisation by the Spanish conquistadors in 1521. The stone was moved 200 yards from the site to the Museum of the Great Temple.