There are few more tantalizing or notorious historical documents than the Vinland map. A faded, yellowing scrap of parchment bearing a faint tracery of lines, the map apparently shows the eastern seaboard of North America--yet it was drawn at least half a century before Columbus reached the New World. Now, in an exclusive investigation, NOVA presents fresh evidence confirming that the map was probably one of the cleverest forgeries of all time.