An unexpected pause in construction has delayed the addition of a third lane to the Pachuca-Huejutla highway near Hidalgo, Mexico. The reason for the scheduling pushback, however, was well warranted—workers accidentally discovered a roughly 1,375-year-old pyramid built during the height of a multiethnic society known as the Metzca lordship.
According to a December 5th announcement from Mexico’s Ministry of Culture and the National Institute of Anthropology and History (INAH), road crews first found evidence of the “San Miguel” site, named after the nearby town of San Miguel Metzquititlán, in early June. Archeologists began excavating portions of the site after highway work halted, eventually unearthing portions of the “Structure 1” pyramid that consisted of five sectors containing at least ten mounds. By the end of their dig, the team recovered 155 artifacts such as shells, ceramics, and stone materials, while also noting evidence of charcoal, charred wood, and lime floors.
Newsletter background image
Get the Popular Science newsletter
Breakthroughs, discoveries, and DIY tips sent every weekday.
By signing up you agree to our Terms of Service and Privacy Policy.
Researchers believe the ruins were likely built by the Lordship of Metztitlán, also known as the “Metzca lordship,” a multiethnic culture that lived in the Sierra Alta area of Hidalgo during the Epiclassic (650-950 CE) and Late Postclassic (1350-1519 CE) eras. In Wednesday’s announcement, Héctor Labra Chávez, Director of Tourism for San Agustín Metzquititlán, explained that there were “no known remnants of pre-Hispanic civilizations in this immediate area” prior to the San Miguel site discovery, and that “Deeper studies are essential to uncover the cultural context of this significant find.”
Experts were working on borrowed time, however. After “exhaustive documentation” of the site using tools such as drone-based photogrammetry, INAH noted that researchers needed to build a roughly 141-foot-long, 38-foot-high, 2.6-foot-thick rock masonry wall along the pyramid’s exposed base. The excavated areas were then reburied to maintain their integrity, but not before coating the exposed areas in geotextiles to better preserve them.
[Related: Mystery language on ancient stone tablet stumps archeologists.]
As Archeology News notes, it unfortunately may be a while before archeologists can return to examining San Miguel. Recent INAH budget cuts will reduce their 2025 funds by 45 percent, curtailing their ability to finance additional projects. Despite this, the recovered materials and structural surveys will provide researchers with information that can help further their understanding of the region.
“This archaeological record provides valuable insights into the human occupation of the Sierra Alta region, particularly in the Barranca de Metztitlán area, where historiography traces settlements back 14,000 years,” the INAH explained.