Aztec Altar Secretly Built After the Spanish Conquest Discovered in Mexico City

Researchers found incense burners, a vessel containing cremated remains and other artifacts in the former capital of Tenochtitlán

Overhead view of excavation site
Excavators discovered the underground ritual site beneath Garibaldi Plaza, formerly part of the Aztec capital of Tenochtitlán. INAH

Archaeologists in Mexico City have found an altar dated to the decades after Spain’s 1521 conquest of the Aztec Empire’s capital, Tenochtitlán. Located in the courtyard of an Aztec home, the altar held a pot containing human ashes and was used to honor the dead, reports BBC News.

Mexico’s National Institute of Anthropology and History (INAH) announced the discovery in November after studying the site for three months. The altar dates to sometime between 1521 and 1610, when the people who lived in the house held a ritual “bear[ing] witness to the ending of a cycle of their lives and of their civilization,” according to a statement translated by BBC News.

The altar was buried about 13 feet beneath Garibaldi Plaza, a central square that regularly hosts festivals. A neighborhood of Tenochtitlán prior to Spanish conquistador Hernán Cortés’ arrival in the region, the area remained home to Aztec residents after the Spanish conquest, Reuters reports.

Ceremonial pot
Ceremonial pot containing cremated human remains INAH

Excavations at the site unearthed artifacts used by the property’s residents over the centuries, including musical instruments and the remains of a kitchen. The home dates to the Late Postclassic period of Mesoamerican history—around 1250 to 1521—but was remodeled sometime after the fall of Tenochtitlán.

The building’s inhabitants took steps to hide the altar from occupying Spanish forces, says Mara Becerra, an archaeologist with the INAH, in the statement. Items found there indicate the site’s sacred status. In addition to the vessel containing cremated remains, the team discovered a cup used to hold the sacred fermented drink pulque and 13 incense burners. 

These incense burners were arranged in a symbolically significant pattern, with some positioned in an east-west orientation and others placed north-to-south. The layout reflected the tonalpohualli, a 260-day Mesoamerican calendar divided into 13-day periods. Aztec cosmology held that 13 heavens were arranged in layers above the Earth. 

figurine from the altar
Arcaeologists unearthed many ceramic artifacts, such as this figure, at the Garibaldi Plaza site. INAH

Designs on the incense burners spoke to their mythic significance. As Stacy Liberatore reports for the Daily Mail, quincunx patterns seen on the objects represent the axis mundi, while the head of a water snake references the underworld.

The discovery arrives as Mexico commemorates the 500th anniversary of the fall of the Aztec Empire. In 1521, Cortés and his small army of 900 Spaniards joined forces with Indigenous people facing oppression by the Aztec, or Mexica, people. The spread of smallpox in Tenochtitlán made it vulnerable to attack, Carlos Viesca-Treviño, a medical historian at Mexico’s National Autonomous University, told Mark Stevenson of the Associated Press (AP) in May. At least half of the city’s 300,000 residents had died by the time the Spanish entered the city, according to some estimates.

In the wake of the conquest, the Spanish worked to replace Indigenous religious practices with Christianity and immerse the region’s inhabitants in Spanish culture, wrote John F. Schwaller, a historian at the University at Albany, for Oxford Bibliographies in 2013. But studies of documents written in the Aztecs’ Nahuatl language, as well as Spanish-language writings by Indigenous authors, argue that the Aztecs and other Indigenous people in the area successfully preserved aspects of their cultures for centuries.

Get the latest stories in your inbox every weekday.