The UNESCO Portal to the Heritage of Astronomy is a comprehensive online platform dedicated to promoting and preserving astronomical heritage worldwide. This initiative, supported by the International Astronomical Union, aims to raise awareness about the cultural significance of astronomy and facilitate the identification and protection of sites linked to the cosmos. Through a rich array of resources, including thematic essays and detailed case studies, the portal assists users in preparing nominations for the World Heritage List and offers insight into various categories of astronomical heritage.

The site features both full and short case studies of remarkable astronomical sites, such as the Chankillo in Peru and the Sydney Observatory in Australia, highlighting their historical importance. Furthermore, the portal houses over 110 outstanding sites recognized for their contributions to the field of astronomy. Users can explore dark sky areas and connect with a global community project showcasing terrestrial locations linked to celestial phenomena. The portal serves as a vital resource for academics, professionals, and anyone interested in the preservation of humanity's astronomical legacy.