The map itself is undated, but there are clues it was created in 1491: It quotes a book published that year, and Christopher Columbus may ... examples of analyzed map images as viewed at different ...

This 1507 map is famous because it is the first known map to call the New World by the name "America." It's highly likely that Christopher Columbus ... is an ultraviolet image of the same portion ...

No authentic map of Columbus was known until Prof. P. Kahle in 1929 found among a number of old charts in the Seraglio at Istanbul a coloured Turkish map of the Atlantic with its islands and coasts.