Archaeologists were left stunned by the discovery of a 43-metre-long engraving of a giant serpent. The rock painting is one of more than a thousand prehistoric engravings discovered by a British-led research team in a remote area of South America. The engravings include depictions of giant centipedes, larger-than-life animals – and gigantic 10-metre-tall human-like figures. Archaeologists believe their discovery is just the tip of the iceberg and that there could yet be a treasure trove containi