The Teotenango archeological monument site is located in the far east of the Cerro de Tetepetl, its construction dates from the Classic period from 250 to 650 AD by people who came to this ancient Chignahuapan region from Teotihuacan (Román Piña Chán called them pre-Teotenancas), and here they found various natural resources for their own consumption as well as for supplying the population of Teotihuacan. The first inhabitants of Teotenango were located in the lower part, while the first works began on top of the hill. Teotenango was most extensively settled by the people of Teotihuacan in the Classic period, by the Matlatzincas in the Epiclassic (650-900 AD) and in the Early and Late Postclassic (900-1550 AD), and finally the Mexica arrived in the Late Postclassic (1476-1550 AD).
One of the site’s most significant aspects is its location: it is in the southwest part of the Valley of Toluca, on a raised geological formation identified as a lava flow, in other words it extends longitudinally with little lateral extension. It comes under the province of the New Trans-Mexican Volcanic Belt, a strip which dates to the Upper Cenozoic, which crosses the Mexican Republic transversally along the 19th parallel, running from the north of Puerto Vallarta in the west to Veracruz in the east. This province is divided into three sub-provinces: Mil Cumbres, the plains and mountains of Queretaro and Hidalgo and the Anahuac lakes and volcanoes. The Cerro Tetepetl forms part of this latter, a sub-province with volcanoes, plains, bodies of water and lake beds.
The lava flow began in the Quaternary, igneous rock made up of emissions which arose at three different times in the Miocene, abruptly ending in faults and fractures which occurred in the Early Pleistocene. The lower part of the flow has a semi-flat deposit plane with a slight slope and this forms part of the area’s flood plain.
The location of the Teotenango archeological site is noteworthy as it demonstrates a strategy to obtain water, control access and security. The chosen site had a natural supply of water, since to the west there are the foothills of the volcano Xinantecatl while the now much reduced lake of Chignahuapan is to the east, in addition to the water deposits which used to lie to the north of the plain. The water supply for humans and agricultural use was guaranteed by these sources.
Access was controlled by limiting the entry of people to the part of the valley leading to its south and southwest regions: Malinalco, Tenancingo, Coatepec de Harinas and to Guerrero, to the southeast part of Michoacan, and to the coastal regions of these states.
Despite having an escarpment, the hilltop location gave the inhabitants of the different cultural periods the security of not being surprised thanks to the angles of visibility to the north, east and south of the valley. The wall in the Late Postclassic would indicate to us that it required a highly efficient security strategy to avoid warlike infiltrations, since the escarpment of the lava flow already represented a challenge to access the summit.
On the other hand the buildings which were constructed on the top of the hill presented a great challenge for the pre-Hispanic builders, who we would now call engineers, architects and town planners, at each of the cultural stages, as well as their adaptation to the rough and irregular shape of the land. To do this, the surface was leveled in determined areas, and the access Plaza was established to lead up to the various groups with pyramidal structures, altars, rooms, ballcourt and other structures, all distributed by level. In the 1970s Román Piña Chán only managed to discover the northern edge of the monument zone bounded by the wall. When walking through the plazas, patios, alleyways and passages you can see the magnificence of these monuments. There are constant reminders of the planning and organization that guided the architectural development evident in each of the periods of construction.
It must be emphasized that the petroglyphs are also evidence of the cultural level attained by the ethnic groups settled in Teotenango. In the 1970s Román Piña Chán (1975) reported the presence of more than 300 engravings, but more than 1500 years of exposure have caused constant deterioration and many have disappeared today as a result of exposure to the elements and human activity. The word petroglyph derives from petro (rock) and gluphē (carving) meaning to carve, sculpt or engrave stone to transmit ideas, signs or knowledge. At Teotenango the engravings were made on rocks of basaltic andesite, and they can be found at the west end inside the walled area. They are carvings on large crags and natural rock outcrops on the surface of the Cerro Tetepetl.
On this site all the petroglyphs have the presence of cavities and stairways in common, which in practice are associated with channels, protuberances and isolated lines which lend a basic composition to the petroglyphs. To these are added anthropomorphic, zoomorphic, phytomorphic and geometric forms, models, bows and arrows, sun and stars, points, ladders and spirals. In terms of their antiquity, Piña Chán determined that they dated after 1162 AD, while some also came from the Colonial period.
The presence of petroglyphs or stone carvings is significant in Teotenango because there is a clear relationship with water. As Piña Chán noted, the cavities examined had the function of collecting dew from the atmosphere or rainwater for use in certain ceremonies or rituals, although he also mentioned that they could also have served to grind certain herbs, fruits or other vegetable products. The channels associated with them also display a certain relationship to water: the circles, the sun and the phytomorphic shapes must be related to the rain, the heat and vegetation while the bows and arrows and zoomorphic forms are to do with hunting and war. These petroglyphs do not point to a highly theocratic group, as was the case at the start of the settlement of Teotenango, but rather they talk of an orientation towards magic and supernatural beliefs, in which the sun, water, rain, wind, animals and narrow caves were the objects of veneration.
One final comment on the location of this magnificent archeological site: the use of the terrain by the ethnic groups settled in Teotenango reflects a concept of settlement designed to meet the most basic of needs, namely water supply. This is evident from the location and from the iconographic elements carved in the rock where water was held. The sun and the wind were elements of nature to which a very strong symbolic meaning was ascribed, and according to Piña Chán they were worshiped through various ritual ceremonies which must have been linked to the agricultural calendar.
