Chankillo
Built over 2,300 years ago is the earliest known astronomical observatory in the Americas. The site features a plaza, thirteen towers that align on a ridge, and a fortified temple surrounded by barricades and defensive walls with false entrances to deter unwelcome visitors.
Chankillo is unique among ancient observatory sites because of its two 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. In July 2021, the Chankillo Archaeoastronomical Complex was officially declared a World Heritage by the UNESCO, which recognize it as a masterpiece of human creative genius and an outstanding example of a type of building, architectural or technological ensemble or landscape which illustrates a significant stage in human history.