Researcher Genevieve Lucet of the National Autonomous University of Mexico has uncovered a previously undocumented Zapotec measurement system in the ancient Mexican city of Mitla.
According to Arkeonews, Lucet analysed nine architectural complexes across the site and found that ancient builders used a mathematical system when constructing temples, palaces and tombs. At the core of the system was a base unit measuring about 8 centimetres in length, which likely corresponded to the width of four fingers held together.
Using multiples of that 8-centimetre unit, architects calculated the dimensions of doorways, columns and interior courtyards. Among the parameters that appeared most frequently across the structures were measurements of 1.84 metres and 1.92 metres.
Lucet examined three architectural groups in the city: the Church Group, the Arroyo Group and the Columns Group. Her findings suggest that differences in the dimensions of the structures were not construction errors, and that architects may instead have deliberately chosen specific proportions depending on the purpose of each space.
Zapotec architecture and Mesoamerican calendar cycles
Lucet paid particular attention to a possible connection between the architectural measurements at Mitla and the calendars of Mesoamerican peoples. Across pre-Columbian Mesoamerica, indigenous civilizations tracked time using a 52-year cycle formed by the alignment of two distinct calendars: a solar calendar lasting 365 days and a ritual calendar of 260 days.
Because of the mathematical relationship between the two systems, their sequences repeated once every 18,980 days, or 52 solar years. In Building 21 of the Columns Group, Lucet identified a notable pattern tied to that cycle.
The combined width of the doorways and columns in Building 21 totals 156 units of 8 centimetres each, a figure that corresponds to three 52-year cycles. Similar numerical ratios appeared in other architectural elements, particularly in the interior courtyards, which according to the researcher may indicate that concepts of time were deliberately incorporated into the design of the buildings.
Sacred geometry in the Mitla burial complex
Located in the Oaxaca Valley of southern Mexico, Mitla served as an important religious and burial centre for the Zapotecs, an indigenous pre-Columbian civilization that flourished in the region for centuries before the arrival of the Spanish. The National Autonomous University of Mexico, the country's largest public research university based in Mexico City, conducts extensive research across the region's archaeological heritage sites.
In the Zapotec language, Mitla was called Lyobaa, which translates as the place where souls rest. Because of that role, Lucet suggested that the architectural proportions may have reflected not only calendar cycles, but also the ancient people's beliefs about death and the afterlife.
In Complex E, for example, an altar was not positioned strictly in the centre of the interior courtyard. Instead, the distances from the altar to the northern and southern sides of the courtyard corresponded to measurement units linked to the numbers 9 and 13.
In some Mesoamerican traditions, those numbers were associated with the nine lords of the night and the 13 lords of the day, and they also played a role in beliefs about the different levels of the cosmos. Lucet suggested that the placement of the altar and the layout features may have held symbolic meaning and been connected to Zapotec religious rituals.
Evidence across other Oaxaca archaeological sites
Traces of a similar measurement system were also identified by the researcher at other Zapotec archaeological sites in the Mexican region of Oaxaca, specifically in Atzompa and Suchilquitongo in the Oaxaca Valley.
However, researchers have not yet established the exact meaning of all the numerical patterns or proved that every identified architectural parameter carried a religious meaning. Even so, the study suggests that the ancient Zapotecs used architecture not only to construct physical buildings, but also to embody their ideas about time, death and the structure of the universe.
