National Geographic Explorer Albert Lin ventures into the Guatemalan jungle to explore how a new high-tech treasure map is revealing tens of thousands of ancient ruins. Now, dozens of archaeologists are heading on a voyage of discovery, exploring lost ruins for the first time in 1500 years. And what they're finding is rewriting the history of one of the world's most mysterious ancient civilisations - the Maya Episodes include… 1 Secrets of the Snake Altar 2 Secrets of the Underworld 3 Secrets of the Sun God 4 Secrets of the Lost City