Archaeologists from the Lyobaa project have confirmed the presence of underground chambers and tunnels beneath the temple in Mitla, Mexico, a significant archaeological site for the Zapotec civilization. This discovery, made using advanced geophysical methods including Ground Penetrating Radar (GPR), Electric Resistivity Tomography (ERT), and Seismic Noise Tomography, reveals a large void under the main altar of the San Pablo Apostol church and a network of tunnels extending in various directions.
Mitla, known as the 'Place of the Dead' or 'Underworld,' served as a burial complex from 100 to 650 AD and is located in the Oaxaca Valley. Historical records, including those from 17th-century Dominican Father Francisco de Burgoa, reference a labyrinth of chambers and tunnels believed to lead to the Underworld.
In addition to the main discovery, researchers identified other geophysical anomalies in the Calvario Group, the Arroyo Group, and the South Group, suggesting the presence of unexplored chambers or tombs. GPR also indicated the potential remains of an earlier monumental stairway beneath the Palace in the Columns Group, which could provide valuable insights into the site's chronology.
The project aims to further investigate these findings through additional probes and excavations. Prior geological studies by the National Institute of Anthropology and History and other institutions suggested that Mitla experienced a significant seismic event in the 15th century, leading to the burial of structures beneath landslide deposits.
Geologist Víctor Hugo Garduño-Monroy previously posited that a magnitude 6 or 7 earthquake caused a landslide that contributed to the decline of the Mitla region, a seismically active area in the Sierra Norte foothills.