Chankillo was built as a fortified temple complex more than 2,300 years ago in the coastal desert of Peru, in the Casma-Sechín river basin. On a hilltop stands a temple ringed by three concentric walls, while on a nearby ridge a line of thirteen stone towers runs north to south. Seen from two observation points, the sun rises and sets over different towers through the year, marking the solstices, equinoxes and the dates in between. This makes Chankillo the earliest known solar observatory in the Americas. It became a UNESCO World Heritage Site, the Chankillo Archaeoastronomical Complex, in 2021.
In 2012, CyArk helped World Monuments Fund document Chankillo, carrying out laser scanning and mapping to develop a detailed 3D model of the site. This record is especially valuable because of the erosion caused over the years by strong winds, humidity, temperature changes and earthquakes.
