A unique ancient observatory
Archaeological evidence indicates that Chankillo may be the earliest known astronomical observatory in the Americas. Built over 2,300 years ago, the site includes a temple, a plaza, and thirteen towers constructed from cut stone. The complex lies in the coastal desert of Peru near the Casma-Sechín river basin. Recent excavations indicated that Chankillo was occupied for a relatively short period of time between the mid-fourth century B.C. and the early first century A.D. but was subsequently abandoned, most likely due to violent conflict. In 2007, Chankillo was identified as an early astronomical observatory.
Chankillo is unique among ancient observatory sites because of its multiple observation points; similar sites around the world contain only one point of astronomical alignment, which does not provide the measurements needed to track the passage of time over a full year. The thirteen towers of Chankillo, situated between two observation platforms, span the entire annual rising and setting arc of the sun, which gradually shifts along the horizon over the course of a year.
The inhabitants of Chankillo would have been able to determine the date with an accuracy of two to three days by watching the sunrise or sunset from the correct observation platform. Using the site as an observatory would have allowed the inhabitants to regulate the occurrence of seasonal events, including planting and harvest times, as well as religious festivals. The archaeological evidence at Chankillo suggests that sun worship existed in the Andes around two millennia before the well-known sun cult of the Inca Empire.
2010 World Monuments Watch addresses threats to site
Chankillo was included on the 2010 World Monuments Watch to raise awareness of the threats facing the site. Strong winds, humidity, and temperature fluctuations in the rough desert climate, as well as earthquakes, have caused erosion, loss of mortar, and weakening of the stone masonry elements of the site. As a result, multiple stones have become dislodged, causing structural instability and the gradual collapse of walls.
After inclusion on the 2010 Watch, WMF supported the Chankillo Revalorization and Sustainable Development Project, partnering with the Instituto de Investigaciones Arqueológicas (IDARQ), and the Ministry of Culture of Peru. The project received financial support from the ANTAMINA mining company, Asociación Ancash, the British Peruvian Cultural Institute, OHL, the Provincial Municipality of Casma, and the U.S.-based Selz Foundation.
Since 2011, the project team has been undertaking excavations to research and document the site, and to establish the legal delimitation of the site. A social component of the program, called Public Archaeology, involved community members and other stakeholders through workshops, polls, and focus groups with the goal of determining long-term management and educational proposals. In January 2013, Chankillo was included on Peru’s Tentative List for inscription on the UNESCO World Heritage List, due in part to our project there.
Restoration of the Thirteen Towers
In 2016, Chankillo received a grant from the U.S. Department of State’s Ambassadors Fund for Cultural Preservation, as well as additional funding from the Selz Foundation. The funding enabled WMF, in collaboration with an international team of architects, archaeologists, conservators, and engineers to perform integral conservation and preventive measures on the thirteen towers at the site. Although Chankillo remains on the Tentative List, one of the goals of our current project is to prepare the site for nomination to the World Heritage List. Therefore, further funding from the Municipality of Casma and WMF also supported the development of a Site Management Plan, a requirement of the World Heritage nomination.