Ok, so the 1960 Basin of Mexico conference was instrumental in defining the nature of prehistoric human activity in the Basin of Mexico. Two archaeologists were assigned the task of figuring out the archaeology of the basin – Millon and Sanders, the former tackling the interior of the city and the latter, the settlement pattern.
Using then-modern 3D photogrammetric mapping methods, Millon produced a contour map of the Teotihuacan and gridded the city into 500 meter blocks, using interior field features as collection units. Although the site has as nucleated core, settlement extends out for an extended distance. In one of the central buildings, Millon discovered a pecked cross with a double circle outline – perhaps representing a cosmogram, a similar symbol appears on the western periphery of the site, and its possible these were features related to making the grid-like layout of the city. Overall, Millon discovered 2200 house compounds build of large rectangular stone walls which were 60 to 185 feet long on a side – these were likely multi-family compounds. As you move away from the site center, households tend to cluster into barrios or neighborhoods. It is also likely, based on bioarchaeological research by Michael Spence, that Teotihuacanos practiced an exogamous matrilocal marriage residence pattern.
Notable barrios outside the city core are the Zapotec Barrio and the Merchant’s Barrio.
Millon’s chronology has been modified by Cowgill’s research, but the phase names have largely been unmodified. Construction at Teotihuacan begins in the Tlaminalopa phase and reaches its apogee in the Xolalpan phase, sometime around AD 200. Distinguishing ceramic phases at the site has been problematic, it is largely agreed upon that by the Metepec phase at around AD 600, the site is largely abandoned. Or rather, that the Teotihuacan sphere of influence collapses.
William T. Sanders’ work in the Basin of Mexico was regionally oriented from an ecological perspective, his goal being to describe how the periphery of the Tehuacan Valley fed the core of Teotihuacan. His research revealed surprisingly little settlement in the Tehuacan Valley, and no obvious site hierarchies in the Basin of Mexico – Teotihucan was not one among many, primer inter pares, but a brightly burning sun in the basin, eclipsing all other sites. Most major sites in the Basin of Mexico date to the Formative period, predating the Classic period. Most of these sites can be defined as hamlets, a notable exception being Cuicuilco, one of the rare circular pyramids in Mesoamerica. The main pyramid at Cuicuilco is 75 feet tall and 400 feet wide at its base; much of the site was covered by pyroclastic flow from the Xichtli volcano at around AD 300. Therefore it looks like Teotihuacan emerges in the Basin of Mexico as a complex polity among other competing smaller groups, perhaps competitive chiefly societies. What was it that Teotihuacan was so good at that it could surpass all the other sites in the basin by several orders of magnitude?