Scientists Discovers 600-Year-Old “Frozen in Time” Lost City in Mexico

The discovery of Guiengola, a 15th-century Zapotec city in southern Oaxaca, Mexico, has fundamentally altered our understanding of its historical significance. Once believed to be merely a fortress housing garrisoned soldiers, Guiengola has now been revealed as a sprawling, highly organized urban center covering 360 hectares (nearly 900 acres). Recent research has identified more than 1,100 buildings, four kilometers (2.48 miles) of defensive walls, a network of internal roads, and a structured layout featuring temples, ballcourts, and distinct neighborhoods for elites and commoners.

Pedro Guillermo Ramón Celis, a Banting postdoctoral researcher at McGill University’s Department of Anthropology, led the study, which has been published in Ancient Mesoamerica. His findings suggest that the city was abandoned just before the arrival of the Spanish, with its inhabitants relocating only 20 kilometers (12.42 miles) away to Tehuantepec, where their descendants still live today. According to Celis, investigating Guiengola’s urban organization on the eve of the Spanish conquest offers a crucial opportunity to understand the Zapotecs' level of political and social complexity. This, in turn, may provide insights into how they negotiated with the Spanish during their encounter.

Ethnohistorical records have long recognized Guiengola as the site where the Mexica (Aztec) armies were defeated by Zapotec forces in the late 15th century. However, the full extent of the site had remained unknown until now. Despite evidence of a dense population, Guiengola had been mischaracterized as a military outpost rather than a thriving city.

A significant breakthrough in uncovering Guiengola’s true scale and complexity came with the use of lidar (light detection and ranging) technology. Lidar employs pulsing laser beams to penetrate dense vegetation and provide detailed three-dimensional topographic data. This method allowed researchers to map the city's structures, which had remained hidden beneath the jungle canopy for centuries. Celis also conducted multiple field visits between 2018 and 2023, confirming the lidar findings on the ground.

His analysis revealed a well-planned city that functioned as more than just a military stronghold. While the settlement featured defensive walls, it also exhibited a complex road network and hierarchical urban organization. However, unlike many Mesoamerican cities where elites dominated urban planning, Guiengola displayed evidence of a relatively egalitarian structure. The presence of 16 plazas and multiple small temples outside the city’s epicenter suggests that communal decision-making played a vital role in shaping the city’s growth. Commoners were not passive subjects under elite rule but actively participated in designing and modifying their living spaces.

The discovery of Guiengola holds deep personal significance for Celis. Growing up in Tehuantepec, he had heard stories about a "lost city" in the region. These childhood tales fueled his passion for archaeology and ultimately led him to investigate Guiengola. His findings confirm that the city, long hidden by thick vegetation, was far more extensive than previously imagined.

Before lidar technology, uncovering such a vast site would have required years of on-the-ground exploration. The jungle’s dense canopy made it nearly impossible to recognize the full extent of Guiengola by traditional methods. However, within just two hours of aerial scanning, lidar revealed a city frozen in time, untouched by the cultural transformations brought by Spanish colonization.

By analyzing the structures identified through lidar, Celis mapped out the size and layout of the remaining buildings. He examined the distribution of space between elite and commoner areas, including the placement of temples and ballcourts. In Mesoamerican culture, ballcourts were highly symbolic, often linked to religious and cosmological beliefs. The ritual ballgame, played within these courts, was associated with myths of death, rebirth, and the underworld, reflecting the agricultural cycles that sustained these civilizations.

Celis emphasized that Guiengola’s remarkable preservation allows for an unparalleled glimpse into pre-Hispanic urban life. Unlike many other archaeological sites that have been heavily eroded or destroyed, Guiengola remains largely intact. Walking through the site, one can still see doorways, hallways, and residential enclosures, making it one of the best-preserved examples of a pre-Columbian city in Mexico.

The revelation of Guiengola as a major urban center challenges previous assumptions about the Zapotec civilization’s political and social structure. Rather than a peripheral settlement, Guiengola emerges as a critical player in late Postclassic Mesoamerican history. It was a place where military, political, and economic forces converged, shaping the Zapotec resistance against the Aztecs and later influencing interactions with the Spanish.

Celis and his team believe that further excavations and studies at Guiengola will provide even deeper insights into Zapotec governance, economic organization, and daily life. As researchers continue to explore this extraordinary site, they hope to shed new light on one of Mesoamerica’s most resilient civilizations.