The Templo Mayor (Spanish for "Main Temple") was one of the main temples of the Aztecs in their capital city of Tenochtitlan, which is now Mexico City. Its architectural style belongs to the late Postclassic period of Mesoamerica. The temple was called the Huēyi Teōcalli [we:ˈi teoːˈkali] in the Nahuatl language and dedicated simultaneously to two gods, Huitzilopochtli, god of war, and Tlaloc, god of rain and agriculture, each of which had a shrine at the top of the pyramid with separate staircases. The spire in the center of the adjacent image was devoted to Quetzalcoatl in his form as the wind god, Ehecatl. The Great Temple devoted to Huitzilopochtli and Tlaloc, measuring approximately 100 by 80 m (328 by 262 ft) at its base, dominated the Sacred Precinct. Construction of the first temple began sometime after 1325, and it was rebuilt six times. The temple was destroyed by the Spanish in 1521 to make way for the new cathedral. Today, the archeological site lies just to the northeast of the Zocalo, or main plaza of Mexico City, in the block between Seminario and Justo Sierra streets.
The site is part of the Historic Center of Mexico City, which was added to the UNESCO World Heritage List in 1987.
After the destruction of Tenochtitlan, the Templo Mayor, like most of the rest of the city, was taken apart and covered over by the new Spanish colonial city. The Temple’s exact location was forgotten, although by the 20th-century scholars had a good idea where to look for it. This was based on the archeological work done at the end of the 19th century and the first half of the 20th. Leopoldo Batres did some excavation work at the end of the 19th century under the Mexico City Metropolitan Cathedral because at this time, the temple was thought to be there. In the first decades of the 20th century, Manuel Gamio found part of the southwest corner of the temple and his finds were put on public display. However, it did not generate great public interest in excavating further because the zone was an upper-class residential area. In 1933, Emilio Cuevas found part of a staircase and beam. In 1948, Hugo Moedano and Elma Estrada Balmori excavated a platform containing serpent heads and offerings. In 1966, Eduardo Contreras and Jorge Angula excavated a chest containing offerings that was first explored by Gamio.