" Traditions, with all their folksy redolences, are relatively safe matters for scholars to speculate about. Maps and nautical charts on the other hand -- especially accurate, sophisticated maps of the kind used by Guzarate to chart Vasco da Gama's course from Malindi to Calicut in 1498 -- are quite another matter. If maps have indeed come down to us containing recognizable representations of Ice Age topography -- as arguably may be the case with the depictions of India and of the long-submerged Sundaland peninsula by Cantino and Reinal and with the depiction of the 'Golden Chersonese' by Ptolemy -- then prehistory cannot be as it has hitherto been presented to us.
If they are what they seem, such maps mean a lost civilization. Nothing more. Nothing less. "

― Graham Hancock , Underworld: The Mysterious Origins of Civilization