Modfied: Monday, July 11, 2011
Welcome to the Cerro Portezuelo Project Page

Collaborative Research at Cerro Portezuelo:

Spanning the Classic to Postclassic at a Teotihuacan Regional Center

Cerro Portezuelo was an important archaeological site in the southeastern part of the semi-arid Basin of Mexico, about 2240 meters (7500 feet) above sea level, near Mexico City. It is now nearly destroyed by urban growth, but significant excavations were carried out by a team from the University of California Los Angeles (UCLA) led by George Brainerd in 1954-55, when the site was in good condition. Brainerd died suddenly in 1956 and H. B. Nicholson was hired by UCLA to replace him and he conducted some additional excavations at the site in 1957. In 1961 and 1962 a brief surface reconnaissance of the site and surrounding areas was conducted under the direction of Dr. Clement Meighan. In the 1960s Frederic Hicks, who had abeen a graduate student on Brainerd's excavations in 1955, and Nicholson drafted excavation reports and classified and tabulated materials, but most of their work remains unpublished. Barbara Branstetter made some compositional studies as a dissertation project. Hicks has recently found time to return to his data analyses.

A large part of the ceramics, mostly pottery sherds, and other artifacts were loaned to UCLA with the understanding with the understanding that they would be more fully studied and returned to the Instituto Nacional de Antropologia e Historia Mexico. In 1992 the UCLA Fowler Museum of Cultural History took over responsibility for the collection and obtained a loan agreement with INAH in 2000. A finding aid to the Cerro Portezuelo Archives at the UCLA Fowler Museum of Culture History Archaeology Facility is available at http://www.oac.cdlib.org/findaid/ark:/13030/kt50001959

In 2005-2010, with support from the National Science Foundation, the Nelson Rockefeller Center for the Social Sciences and the Claire Garber Goodman Fund of Dartmouth College, and the School of Human Evolution and Social Change of Arizona State University, Dr. George L. Cowgill (ASU), and Dr. Deborah Nichols (Dartmouth), began a collaborative project to complete an adequate study of the materials and field records, making use of current knowledge of Central Mexican materials, methods of data analysis, and unresolved historical and theoretical issues. They were principally assisted by Drs. Destiny Crider and Sarah Clayton who at the time were graduate students at ASU's School of Human Evolution and Social Change. Important contributions to the project were also made by Fred Hicks and specialist consultants William Parry of Hunter College (obsidian), Martin Biskowski of California State Sacramento (ground stone), Hector Neff of California State Long Beach (Neutron Activation Analysis), Wendy Teeter, curator, Fowler Museum, UCLA (faunal materials), Christopher Garraty of the Cultural Resource Management Program (CRMP) at the Gila River Indian Commuity (Aztec ceramics), Michael Spence and Christine White of the University of Western Ontario (skeletal analysis and stable isotopes of bones and teeth), and Janet Montoya of ASU (ceramic figurines). Several undergraduates from ASU and Dartmouth also provided valuable assistance. Both Christopher Garraty and Destiny Crider included analysis of some ceramics from Cerro Portezuelo in their ASU dissertations.


The UCLA surveys and excavations at Cerro Portezuelo were undertaken with permission of the Instituto Nacional de Antropologia e Historia, Mexico. The 2005-2010 studies of the Cerro Portezuelo artifacts and excavation data were supported by the National Science Foundation under Grants No. 0514187 (Dartmouth College), 0513979 (Arizona State University) and 0504015 (Missouri University Research Reactor).

Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Additional support has been provided by the Claire Garber Goodman Fund, Dartmouth College, Rockefeller Center Urban Studies Grant, Dartmouth College, the School of Human Evoluation and Social Change, Arizona State University, the Archaeological Research Institute, Arizona State University and the Fowler Museum UCLA.

Ceramic Analysis          

In August 2005 most of the materials at UCLA were moved to ASU by Crider and Clayton. Our ceramic analyses are adding much new data, enabling comparisons with current data for all periods from nearby sites and making it possible to relate the categories used by Hicks in his earlier studies to recent categories and categories we are developing. Over 800 pottery specimens have been sent to the University of Missouri Research Reactor (MURR) for instrumental neutron activation analysis (INAA). The results will be analyzed by Neff to determine compositional group affiliations, drawing on MURR’s large Basin of Mexico database, from which several subregional groups have been established in previous work.

Recent Updates

See the abstracts for 2008 SAA Symposium on Cerro Portezuelo  >

Introduction to Cerro Portezuelo

Occupation at Cerro Portezuelo began by AD 1 (earlier than had been thought) and continued into Early Colonial times in the 1500s. This long record makes the site highly strategic for study of a number of issues.

Cerro Portezuelo is about 40 kilometers south of the immense city of Teotihuacan, which dominated the entire Basin of Mexico and was highly influential beyond that, from before AD 150 until its collapse in the 600s. Cerro Portezuelo was one of a few Teotihuacan Period major regional centers within the Basin. Teotihuacan has been intensively studied over the past century, but relatively little work has been done on these regional centers, so Cerro Portezuelo offers an unusual opportunity to learn about how Teotihuacan and one of its regional centers related to one another (it is likely that different centers had somewhat different relations).

Some Research Questions

Questions we address include (1) did Cerro Portezuelo obtain many materials from Teotihuacan or largely produce its own? (2) how tightly does it conform to Teotihuacan decorative and technological styles? (3) did local artisans have the full range of skills as seen at Teotihuacan or were they less sophisticated? (4) how does the wealth gradient compare with Teotihuacan —was there a much lower proportion of elites? (5) does it look highly administered politically and/or economically or relatively autonomous?

Other much-debated issues concern the transition following the collapse of the Teotihuacan state. Was there a high degree of continuity in culture and population or was there considerable cultural discontinuity and possibly even sizable migrations of newcomers into Central Mexico? Surprisingly different interpretations of data from Teotihuacan itself are hotly debated, and, in any case, it is important to note that regional centers appear to have had different experiences. In the 1950s Cerro Portezuelo seemed to provide evidence of a gradual transition, but we are reassessing this in the light of more recent knowledge.

A related issue is that of response and reformulation following collapse of the Teotihuacan state. It seems likely that the immediate result was political and economic fragmentation ca. AD 650-800, and then (ca. AD 800-1000/1100) building larger polities with centers just outside the Basin, at Tula to the northwest and Cholula to the southeast. How did Cerro Portezuelo and other sites within the Basin relate to these new influences? Cerro Portezuelo grew into a much larger settlement than before and may have been capital of an independent polity in the early part of this period.

We are pursuing such questions further for another period of apparent political fragmentation, ca. AD 1000-1300, and then increasing growth of larger states, leading to the Aztec Empire. Cerro Portezuelo lay on the boundary of the Acolhua and Chalca confederations and had a more substantial occupation in the Middle and Late Postclassic than previously recognized, and continued to be occupied into the Early Colonial period. The fact that occupation runs through the entire Postclassic allows us to look at changing political and economic relations among city-state centers, the larger regional states centered on Tula and, and the expanding Aztec Empire during the last century before the Spanish Conquest.

Other Impacts

We are creating an electronic database to make our data and research results widely available. Our project contributes to archaeological cooperation between the US and Mexico. We are providing graduate and undergraduate students an opportunity to be active participants in research and to learn at first hand methods of artifact analysis that are essential for future investigations in Central Mexico.