Archaeologists recently found the lost ruins of a ceremonial temple—covered in sand and 4,000 to 5,000 years old—in northwestern Peru. The oldest portion of the site features not only the up-to-5,000-year-old walls, but also various architectural features that help define the site as a ceremonial temple. “It was amazing,” said Muro Ynoñán, according to a statement from the Field Museum in Chicago. “It was so surprising that these very ancient structures were so close to the modern surface,” Muro Ynoñán said. “The people here created complex religious systems and perceptions about their cosmos,” Muro Ynoñán said.