The earliest adobe monumental architecture in the Americas

This study documents the previously unrecognized technological evolution of pre-Hispanic Andean adobe bricks, the central component of this region's millennia-long earthen architectural tradition. Multidisciplinary geoarchaeological research in northern Peru shows that the earliest known standing adobe brick architecture in the Andes dates before 5,100 calendar years B.P., using adobes cut from natural clay deposits created by El Niño flooding. Other than the deliberate shaping of the material, they were unmodified but were used like later adobe bricks. Later pre-Hispanic adobe bricks were made more durable by mixing clay with temper and water. The beginning of adobe architecture in the Andes is associated with the construction of early monumental structures for communal ceremonies and the rise of social complexity.