Chankillo was built as a fortified temple complex over 2,300 years ago in the coastal desert of Peru, near the Casma-Sechín river basin. The monumental complex was constructed from cut stone and includes a fortified temple, a plaza, and 13 towers, which are now thought to be an astronomical observatory. Excavations at Chankillo have indicated that the site was occupied sometime between the mid-fourth century B.C. and the early first century A.D. for a relatively short period of time and was subsequently abandoned, most likely due to violent conflict.
Chankillo was identified as an observatory in 2007, creating greater interest in the site. Strong winds, humidity, temperature fluctuations, and earthquakes have caused erosion, loss of mortar, and weakening of stone masonry to the historic elements of the site. As a result, stones have cracked and fallen out, causing structural instability and the gradual collapse of walls.