Entering the Underworld: Subterranean Chamber and Tunnel Found Beneath the Pyramid of the Moon (Teotihuacán)

Teotihuacán is without a doubt one of the most popular archeological centers in all of Mexico. Just last year, according to official statistics, it received over 4 million visitors from all over the world, eager to endure the droves of vendors and the hot sun just for a chance to marvel at what is considered to be the most important city in all of Mesoamerica –perhaps all of the Americas– during the Classic period (250 CE to 900 CE).

Which is why it’s so surprising and encouraging to find out Mexican scientists continue to make important discoveries at this precolombine site. Last week archeologists from the National Institute of Archeology and History (INAH), along with experts from the Geophysics Institute at the National University (UNAM), announced the discovery of an underground chamber of approximately 15 meters in diameter, located 8 meters below the Pyramid of the Moon, which is part of the Plaza of the Moon and is located at the northern end of the massive ‘Avenue of the Dead’ (“Calzada de los Muertos”) which crosses the main Teotihuacan complex.

The pyramid’s original construction took place between 200 and 250 CE. Since then, it underwent at least 6 renovations in which the original inhabitants of Teotihuacán aggrandized the structure like an onion –contrary to popular belief, the city was NOT built by the Aztecs, and in fact when they arrived to Mexico’s central valley they found the city already in ruins, which nevertheless impressed them so much they concluded ordinary mortals couldn’t have possibly built it, which is why it was named Teotihuacán  (“the place where men became gods”).

Doctor Verónica Ortega, head of the project which found the chamber, also announced the discovery of an additional underground tunnel which leads to the southern of the Plaza of the Moon, although the archeologists suspect a secondary entrance could be located elsewhere. Both subterranean structures are thought to have been used for ritual/initiatory purposes, meant to symbolize the underworld where the gods reside. Perhaps such rituals took place when a new regent or king was elected, or when an old one died and his or her remains were deposited below so they could take their rightful place among the gods –the finding of a royal tomb inside Teotihuacan has never taken place, and has become something of a holy grail for Mexican archeology. Perhaps the chamber beneath the pyramid of the Moon could contain such funerary remains, but the main objective of the new study is to understand its ceremonial importance instead.

“These large offering centers constitute the sacred core of the city of Teotihuacan, which is why all the people considered it the mecca of civilization,” doctor Ortega explained during the press conference announcing the discovery. “Hence why anything that can be found in the interior [of this new chamber] could help unravel the relations this old metropolis had with other regions of Mesoamerica.”

The finding of these new chamber and tunnel –which were the result of a study conducted in 2017 using electric resistivity and tomography techniques– means that all of the three main buildings in Teotihuacán –the pyramid of the Sun, the pyramid of the Moon and the temple of Quetzalcóatl– have underground passageways beneath them.

In the 1970’s archeologists found the entrance to a large cave of possible natural origin under the pyramid of the Sun, and at the end of it there are four chambers in a flower-like arrangement, which hint at how the ancient people of Teotihuacán might have modified the original cave so it resembled their origin myths (Chicomóztoc, the place of the seven caves, is the mythical place of origin of the inhabitants of Mexico’s central valley). It’s very possible that ancient shamanic rituals took place inside this cave even before Teotihuacán was founded (almost 2000 years ago), and that its religious importance prompted the construction not only of the pyramid above it, but the entire city complex. Despite its name, archeologists believe the pyramid of the Sun was actually dedicated to Tláloc, the god of rain –evidence of this is the discovery of sacrificed children, which is resemblant of how the Mayas also offered children to Chac (their god of rain) by throwing inside cenotes, the large natural wells which they took as entrance to Xibalbá, the underworld.

In 2003, archeologist Sergio Gómez found another underground tunnel beneath the Temple of the Plumed Serpent (Quetzalcóatl) totally by chance. The passage had been deliberately sealed by the inhabitants of Teotihuacán some 1700 years ago. In 2009 the archeologists started to study the tunnel through the use of robots –just like the Germans studied the inner chambers inside the great pyramid of Cheops with the Upuaut project— and discovered its walls were covered with pyrite, which would have made them sparkle like stars when lit with a torch. They also found remnants of mercury, which prompted some to compare it with the pyramid-like mausoleum of the first Chinese emperor.

3 ancient buildings inside the most powerful urban center in the Mesoamerican world, and beneath all of them underground tunnels and chambers, which were more than likely used for the most sacred ceremonies of this enigmatic nation. It’s hard not to wonder if these mesoamerican representations of the underworld were not connected to the altered states of consciousness studied by Paul Devereux, and other researchers in the oft-ignored field of Archaeoacoustics.

In any case, it’s a safe bet to conclude this will not be the last major discovery to be made in the place where men became gods.