The Piri Reis map

There's an ancient map that is quite intriguing. It is extremely accurate and charts much of the land that had yet to be discovered. Even more remarkably, it charts antarctica land mass which was not even possible until ground penetrating radar was invented that let us peer beneath the mile-thick ice covering.

The Piri Reis map is a famous pre-modern world map compiled in 1513 from military intelligence by the Ottoman-Turkish admiral and cartographer Piri Reis. The half of the map which survives shows the western coasts of Europe and North Africa and the coast of Brazil with reasonable accuracy. Various Atlantic islands including the Azores and Canary Islands are depicted, as is the mythical island of Antillia and possibly Japan. The map has been used to claim an ancient knowledge of an ice-free Antarctica, transmitted either from extra-terrestrials or an Ice Age civilization. These claims are generally considered to be pseudo-scholarship, and some scholarly opinion is that the region sometimes thought to be Antarctica is more likely to be Patagonia or the Terra Australis Incognita (Unknown Southern Land) widely believed to exist before the Southern Hemisphere was fully explored. The undisputed historical importance of the map lies in its demonstration of the extent of Portuguese exploration of the New World by approximately 1510, and in its claim to have used Columbus's maps, otherwise lost, as a source.