To the Aymara people of the Andes, Lake Titicaca is a mystical being. It's a belief that dates back hundreds of years to the Inca—and beyond, as evidenced by treasure pulled from the lake's depths, per Live Science. Divers have discovered gold medallions marked with a ray-faced deity, a turquoise stone pendant, and a puma carved from lapis-lazuli—all dating to the pre-Incan Tiwanaku, who flourished between AD 550 and AD 1000. "The history that these objects tell us is exceptional," archaeologist Christophe Delaere tells the Guardian. Indeed, the artifacts were found on an underwater reef that once stood as an island near the lake's center. As it offers panoramic views of the lake and surrounding mountains, "it is not surprising that the Tiwanaku elite appropriated this space for costly and highly charged ceremonies," researchers write in PNAS.
Charcoal, incense holders, ceremonial dressings, shells carried 1,200 miles from the Pacific Ocean, and bones of young llamas sacrificed—all dating between AD 794 and 964—certainly suggest religious offerings. Combined with other evidence, they indicate "there was probably a series of pilgrimages or processions around the lake," one researcher tells the Guardian. The religious tradition likely helped the Tiwanaku state expand to eventually include parts of Peru and Chile, reports National Geographic. Belief in a common tradition would've brought a sense of unity and a reduced threat of warfare, says study author Jose Capriles. At the same time, "these deities that people are creating are becoming institutions that govern behavior," he says. "If you're bad, you are going to get punished by the chief's deity." (Lake Titicaca recently saw mass deaths.)