China map lays claim to Americas

A map due to be unveiled in Beijing and London next week may lend weight to a theory a Chinese admiral discovered America before Christopher Columbus. The map, which shows North and South America, apparently states that it is a 1763 copy of another map made in 1418.

If true, it could imply Chinese mariners discovered and mapped America decades before Columbus' 1492 arrival. The map, which is being dated to check it was made in 1763, faces a lot of scepticism from experts.

See also this Economist version of the story and a rebuttal by an Asian historian.