MEXICO CITY.- Archaeologists working at the heart of Mexico City have uncovered evidence of what may have been one of the most spectacular religious ceremonies ever staged in the Mexica capital of Tenochtitlan.

Researchers from the Proyecto Templo Mayor (PTM) announced that three recently studied ritual deposits—Offerings 186, 187 and 189—appear to be part of a single, colossal ceremony carried out during the reign of Motecuhzoma Ilhuicamina, the powerful huei tlatoani who ruled Tenochtitlan between 1440 and 1469.

The findings were presented on February 26, 2026, during the lecture series “La arqueología hoy,” organized by El Colegio Nacional.

A circle finally closed

Three years ago, the team revealed the discovery of a tepetlacalli—a Nahuatl term for a stone chest—containing 15 Mezcala-style greenstone figurines. At the time, it was an extraordinary find. Now, with two additional deposits of similar characteristics uncovered and analyzed, archaeologists believe they are looking at something far more ambitious: a coordinated, large-scale offering placed around the Templo Mayor as part of a single ceremonial event.

Leonardo López Luján, director of the PTM, invited the public to imagine the scene: dozens of priests and thousands of worshippers gathered around the towering pyramid, placing sculpted relics, shells, seeds, sawfish rostra, copal resin and bitumen at the same moment.

For decades, scholars suspected that six offerings dating to Stage IVa of the temple’s construction—corresponding to Ilhuicamina’s reign—were originally arranged in a symmetrical pattern. Earlier discoveries in the 1970s and 1990s hinted at this possibility. Now, with the most recent excavations, archaeologists say they have “closed the circle” for the first time, confirming that all six deposits were placed during the same building phase.

War spoils transformed into sacred offerings

The scale of the operation is staggering. The six stone chests held 83 anthropomorphic figurines carved in greenstone, some weighing up to a metric ton when combined with their containers and associated sculptures. Moving them would have required ropes, levers and wooden rollers—no small feat in the 15th century.

What makes the discovery especially striking is the unusual concentration of Mezcala-style figurines. According to López Luján, they do not appear in such abundance before or after this moment in the Templo Mayor’s history.

The likely explanation lies in politics and conquest. Motecuhzoma Ilhuicamina was the first Mexica ruler to expand imperial control beyond the Basin of Mexico. Territories such as Tlaxco and Tlaxmalac, in what is today northern Guerrero, were subdued in the late 1440s. The figurines may represent war trophies—objects taken from conquered regions and ritually reinterpreted at the heart of the empire.

Many were repainted in red and white pigments and modified with attributes associated with the rain god Tlaloc, to whom part of the Templo Mayor was dedicated. Through ritual, foreign objects were transformed into sacred symbols of imperial power.

Shells from distant seas

The offerings also contained more than 4,000 marine elements—primarily snails of the species Nerita scabricosta and Hexaplex brassica. Most originated from the Atlantic coast, hundreds of kilometers away.

Remarkably, some shells retained traces of their periostracum, a delicate organic layer usually lost soon after a mollusk dies. This suggests the Mexica may have transported the creatures alive in saltwater containers from the coast to Tenochtitlan, underscoring the logistical sophistication of the empire.

Preserving fragile history

Conservators faced enormous challenges. The stone chests, measuring roughly 50 centimeters in height and width, had to be protected immediately from sunlight and carefully stabilized over six to eight months. Sculptures were cleaned with cotton swabs to remove sediment, and natural fixatives were applied to preserve surviving pigments.

The newly studied offerings will now be safeguarded at the Museo del Templo Mayor, where they will remain available for further research. Plans are also underway for a future exhibition that would bring together all six deposits for the first time, offering visitors a rare glimpse into the ceremonial heart of Mexica religion.

More than five centuries after the fall of Tenochtitlan, the discoveries beneath modern Mexico City continue to reshape our understanding of imperial power, sacred performance and the sheer theatrical scale of ritual in the Aztec world.