The Gateway of the Sun is an ancient stone archway located near the city of Tiwanaku in Bolivia. It is believed to have been constructed by the Tiwanaku civilization around 300 AD. The structure is made from a single block of andesite and features intricate carvings, including depictions of the sun god and other symbolic figures. This monument is significant for its alignment with the sun during the winter solstice, suggesting it may have had astronomical or religious importance. The Gateway of the Sun is often associated with the broader cultural and spiritual practices of the Andean civilizations, highlighting their advanced understanding of astronomy and architecture.