Pre‐Classic Olmec frontier site in the Amatzinac Valley of eastern Morelos. Two natural igneous intrusions rising to over 300 m above the valley floor dominate the whole area and must have been sacred places throughout much of prehistory. At the base of the sheer sides of the central mountain are a series of Olmec bas‐ reliefs carved on boulders. The most elaborate shows a woman sitting on a throne, holding in her hand a ceremonial bar. She sits within the mouth of the Olmec earth monster, as though within a cave. Also at the foot of the central mountain there are platform mounds and terraces. Excavations by David C. Grove and Jorge Angulo in the 1960s show that the site was founded about 1500 bc and reached its peak during the Cantera Phase of the middle Formative, 700–500 bc.
Chalcatzingo had many Olmec features in addition to the rock carvings, including crypt burials, human sacrifice, and the use of cultivation terraces. There are no local antecedents for the Olmec elements at the site so some kind of population movement must be envisaged.
D. C. Grove, 1968, Chalcatzingo, Morelos, Mexico: a reappraisal of the Olmec rock carvings. American Antiquity, 33(4), 486–91;D. C. Grove et al., 1976, Settlement and cultural development at Chalcatzingo. Science, 192, 1203–10