On the northern coast of Peru, researchers have discovered the oldest adobe architecture in the Americas, built with ancient mud bricks carved from natural clay deposits created by flooding caused by El Niño.

According to the international research team led by archaeologist Ana Cecilia Mauricio, the pre-Hispanic bricks – carved from sedimentary layers rather than created by mixing clay, tempering and water – date the invention of the adobe architecture more than 5,100 years ago.

In the Andes, the first monumental adobe structures are associated with communal ceremonies and rising social complexity, the team notes.

The research began when Mauricio held an interdisciplinary doctorate. student at the Institute of Climate Change at the University of Maine. Her thesis 2015 the advisers were UMaine anthropology professor Dan Sandweiss and Alice Kelley associate research professor at the Climate Change Institute. Mauricio also obtained a master’s degree from UMaine.

The results were published this month in the Proceedings of the National Academy of Sciences and the review Nature pointed out the research. Kelley and Sandweiss are co-authors of the article.

Mauricio, now professor of archeology at the Pontifical Catholic University of Peru, has been conducting archaeological and geoarchaeological studies at the Los Morteros site and the Pampa de las Salinas archaeological complex in the Lower Chao Valley since 2012. Los Morteros was considered a burial mound until a research team from the UMaine led by Sandweiss and Kelley uses ground penetrating radar in 2006 and 2010 to show evidence of buried architecture.

Mauricio’s research has shown that the mound once considered a natural phenomenon is the site of monumental architecture. Evidence of human occupation included stone hearths containing small fish bones, charcoal, and scallop shells, and rooms made of adobe bricks, with plaster walls and clay floors.

A press release from Pontificia Universidad Católica del Perú is translated below:

With more than 5,100 years of antiquity, the oldest adobe architecture on the continent was discovered in the Chao Valley, La Libertad
An investigation of the Los Morteros site in the Chao – La Libertad valley uncovered the oldest monumental adobe construction in America. Rammed earth structures date from 5,500 to 5,100 years ago and were built almost a thousand years before Caral.

November 2021 – In a study recently published in the prestigious scientific journal PNAS, a multidisciplinary team of researchers from the Pontifical Catholic University of Peru (PUCP) and the University of Maine in the United States, documents the technological evolution until then unknown to the pre- Hispanic Andean adobe, central element of the ancient architectural tradition of the land in this region.

This geoarchaeological investigation carried out on the site of Los Morteros, in the Chao valley, has revealed the oldest adobe architecture on the continent dating back more than 5,100 years. These buildings, with monumental characteristics, were made from adobe carved from natural deposits of clay, created by the floods caused by the El Niño phenomenon. This research has discovered that the beginning of adobe construction technology is linked to the use of natural deposits.

Over time, pre-Hispanic adobe was made more durable by mixing clay with quenching and water. This discovery suggests that the beginning of adobe architecture in the Andes was associated with the construction of monumental structures for communal ceremonies and the emergence of social complexity.

Ana Cecilia Mauricio, professor of archeology at the Pontifical Catholic University of Peru and director of research, underlines that the importance of this site is due to the fact that it contains key information to understand the origin of monumental constructions and rammed earth construction technology.

The adobe constructions of Los Morteros would have had similar functions to the pyramids of Caral, but they were built almost a thousand years earlier and are on a smaller scale, considering their age.

“In this study, we propose that adobe architecture has become an important Andean architectural tradition, after a long period of experimentation and technological evolution, both in its form and in its composition”, indicates the professor of archeology. at the PUCP.

Rammed earth structures
The article “The First Monumental Rammed Earth Architecture in the Americas” emphasizes that rammed earth or mud bricks are constructive elements that have defined the main architectural traditions of the Andes over thousands of years. From the Moche Pyramids and the ancient city of Chan Chan in pre-Hispanic times, to the Spanish mansions of the colonial period and the rural houses of contemporary South America, adobe has been the centerpiece of the Andean architecture.

The discovery of the remains of an ancient monumental building built mainly in adobe on the site of Los Morteros (lower Chao valley, northern coast of Peru), places the invention of adobe architecture more than 5,100 years ago . The unique composition, internal and chronological structure of the adobes of Los Morteros can be defined as the construction of the oldest monumental adobe building in America.

Contact: Margaret Nagle, [email protected]