Have Archaeologists Found Lyobaa, the Zapotec Land of the Dead?

Beneath monumental stone structures discovered at the archaeological site of Mitla in the southern Mexican state of Oaxaca, it has long been believed that the ancient Zapotec people built a huge and complex labyrinth of chambers and passageways. This network of tunnels was ultimately supposed to lead to the entrance of the Zapotecan underworld or Land of the Dead, which was known as Lyobaa.

In search of the truth about this legend, a team of Mexican archaeologists launched an ambitious exploration project at Mitla in 2022, relying on non-invasive geophysical survey tools to see what really lies underneath the ancient site. The Project Lyobaa research team has recently released its report on the first season of its survey, and what they found confirmed the presence of a vast Zapotecan underground complex.

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Their study has also revealed fascinating details about what the various subterranean structures actually look like, revealing important information about a spiritual mecca built by and for the Zapotecan people who occupied southern Mexico during the pre-Columbian era.

Modern Technology Reveals Underground Entrance to Lyobaa

Officially launched in 2022, Project Lyobaa is a collaborative effort sponsored by the Mexican National Institute of History and Anthropology (INAH), the National Autonomous University of Mexico (UNAM) and the Association for Archaeological Research and Exploration (the ARX Project).

Instead of relying on traditional excavation methodologies to explore the underground region at the ancient Mitla settlement, the researchers used geophysical scanning technologies to search for hidden underground spaces, eliminating the need for any digging. The technologies deployed included Ground Penetrating Radar (GPR), Electrical Resistivity Tomography (ERT) and Seismic Noise Tomography, each of which uses electromagnetic emissions to penetrate the surface of the earth and generate images of what lies on the other side of that physical barrier.

Combining the results of their intensive scanning procedures, the Mexican researchers produced composite 3D models of the subterranean world found just below the surface at Mitla.

One of the 3D models of the spaces underneath Mitla. (©Marco M. Vigato / Arx Project)

Most significantly, the findings of the geophysical survey absolutely confirm the presence of multiple underground chambers and tunnels winding their way through the earth beneath a set of structures known as the Church Group (there are five sets of above-ground structures at Mitla, and this one features a Catholic church constructed in the late 16th century).

Documents preserved since Spanish colonial times identified this area as the entrance to the underground temple of Lyobaa, where Zapotecan worshippers went to commune with gods and ancestral spirits.

The surveys also explored areas beneath the most elaborate structure at the site, which is known as the Palace of Columns and is part of the so-called Columns Group of structures. Here the scans returned imagery that revealed details about the earliest phase of construction of this building. They also detected geophysical anomalies that the researchers believe are probably buried tombs.

The researchers will continue to study the results of their initial explorations, looking for details that might have been missed during the first analysis. Nevertheless, they are delighted by what they’ve been able to discover so far.

“These findings will help rewrite the history of the origins of Mitla and its development as an ancient site, as well as providing valuable information for the management and prevention of seismic and geological risk in the area,” the researchers said in a statement released by the ARX Project.

The Catholic Church at Mitla. (©Marco M. Vigato/ Arx Project)

Christian Missionaries Sealed the Entrance the Land of the Dead

The Zapotec site at Mitla in Oaxaca features an impressive collection of monumental structures decorated inside and out with mosaics made from pieces of polished stone. Evidence shows the site was inhabited by 3,000 BC or possibly earlier, although it was during the first half of the Post-Classic Period (900 to 1200 AD) that the Zapotec culture reached its peak of prosperity, earning its reputation as one of the greatest of all Mesoamerican civilizations.

Most of the structures found at Mitla were constructed in Post-Classic times, and presumably that is when the underground passages and chambers were carved out as well. Writing in 1674, long after the Zapotec people had been conquered by the Spanish, a Dominican father named Francisco de Burgoa told of explorations of the underground world at Mitla by a group of missionaries.

Providing a wealth of details, the group reported finding a sprawling subterranean temple that featured four interconnected chambers. Inside the chambers, they said, were the tombs of Zapotec kings and priests. At the end of the last chamber, they said there was a stone door that covered the entrance of a deep cave that extended far below ground. This cavern contained a separate network of passages, its high roof supported by tall stone columns.

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The Christian missionaries were apparently more alarmed than awestruck by their discovery of this incredible underground “city,” which had been constructed by followers of the indigenous religion. On their orders, the entrances to the underground labyrinth of Lyobaa were all sealed, presumably to prevent the surviving Zapotecans from entering in search of their Land of the Dead.

Sometime afterward, a Catholic church was built over the primary entrance to the underground complex of Lyobaa. Local tradition claimed that the main altar of the church concealed that entrance, and amazingly enough the geophysical survey of the site revealed that this was true.

A 3D model superimposed in position over the Church at Mitla. (©Marco M. Vigato / Arx Project)

A large void was found just beneath the altar, extending to the west and northwest, and two east-west passages were also detected entering the void from an easterly direction. These two passages were determined to be five and eight meters (16 and 26 feet) below the ground.

The area underneath the Palace of Columns and the other buildings in the Columns Group was also scanned, but the researchers didn’t find a similar network of tunnels and chambers. What they did discover was a stairway leading down to a pair of doors just beneath the palace floor, along with chambers identified as tombs at a greater depth. The buried stairway suggests that construction may have begun on the Palace of Columns in the late Classic Period (250 to 900 AD), before being finished in Post-Classic times, when the current bottom floor was constructed.

The Search for the Zapotecan Underworld Continues

In September of this year, Project Lyobaa will launch a new round of geophysical scans at Mitla. Areas beneath the remaining groups of buildings to the north and west of the Church Group and Columns Group will be surveyed, to ascertain the true extent of the underground complex constructed by the Zapotecans and understand whether the subterranean complex is larger than their initial estimations.

Top image: A corridor at the Lyobaa underground network at Mitla. Source: ©Marco M. Vigato / Arx Project

By Nathan Falde