Structure 16 is a large low platform located about 300 meters northeast of structure 17, along the road toward the center of the village of Calixtlahuaca (the major road through the village runs along the north side of structure 16). García Payón uncovered the walls of the platform, and one can still see the fine stonework (similar to that visible in structure 1) on most of the four sides. He conducted only limited testing on top of the platform, and the nature and function of this structure is unknown. Although a ballcourt is perhaps the most likely candidate, test excavations (by García Payón and later by Román Piña Chán) have been unsuccessful in determining the form or use of structure 16.
BURIALS AND OFFERINGS
José García Payón excavated a large number of human burials at Calixtlahuaca, most of which were apparently accompanied by offerings of goods. He described some of the burials and offerings briefly in his publications, but complete descriptions were never published (perhaps there is information in the lost volume of illustrations). The only image of a burial offering published by García Payón is shown in figure 13. Many of the human burials were secondary burials (i.e., after a period of disintegration of the body, the bones were gathered up and reburied), and a large number of the long bones were cut with notches (fig. 13). Such bones were used in Aztec ceremonies as musical instruments.
The left image in figure 13 shows two ceramic vessels included as offerings with the burial: a tripod plate inverted over the skull, and a globular jar. Most of the ceramic vessels and other objects from burial offerings are stored today in the Museo de Antropología in Toluca (see below). In 2002 I studied over 1,200 of these vessels; some of the typical vessel forms are shown in figure 14. Objects of bronze alloys (copper alloyed with tin and/or arsenic) were also common burial goods; the bells shown in figure 15 are good examples. The bronze objects were probably manufactured in western Mexico and traded to Calixtlahuaca (Hosler 1994), although it is possible that there was a local tradition of copper metalworking in the region.
URBAN PLANNING AND LAYOUT
There are several notable aspects of the planning and layout of the ancient city of Calixtlahuaca. First, the spatial distribution of public architecture is radically different from other Aztec-period cities in central Mexico. At most of these cities the temples, palace, and other large stone buildings are clustered together in a central district, but at Calixtlahuaca these structures are scattered throughout the site. Furthermore, Calixtlahuaca lacks a large formal public plaza, a basic feature of urban layout at most Mesoamerican cities. These and other features of spatial layout at Calixtlahuaca remain enigmatic and are the target of ongoing research at the site.
A second notable feature of urban planning at Calixtlahuaca is the role of stone terraces. Terracing has a long history as an intensive agricultural technique in Mesoamerica. The rapid growth of population during the Aztec period was accompanied by the construction of many thousands of stone terrace walls on hillsides throughout central Mexico. Although a close association between Aztec terracing and rural settlement has been documented in many areas, Calixtlahuaca is the only large urban center in which the majority of urban land was covered with terraces. Settlement covered the northern slopes of Cerro Tenismo, all of which were modified by construction of stone terrace walls. These can be seen on the air photos of the site (figs. 2, 3). Remnants of these walls survive in many parts of the site (fig. 16). Settlement only extended a limited distance onto the plain at the base of the hill.
With the entire slope of the mountain converted into a mosaic of stone terraces, Calixtlahuaca presented an impressive view to anyone approaching the city from the north or west. Most of the large temples were also visible from afar, including structure 3 and the temples of groups B and E.
The Museum at the Site
The site museum, owned and run by the city of Toluca, was built with a circular form like structure 3 at the site. There is a small collection of objects from the excavations of José García Payón,