Chankillo is a 2,300-year-old archaeological ruin located at a desert valley in northern Peru. The site consists of 13 towers that align on a ridge. These towers dates between 250 and 200 BCE. They are positioned in such a way that they match precisely that movement of the Sun throughout the seasonal year. Together these towers are known as the oldest solar observatory in the Americas.
The site was recently attained the UNESCO world heritage status. Apart from the 13 towers, the site consists of a temple and a plaza. It is located close to the Casma-Sechín river basin.