How many centuries before Columbus did the Vikings discover America?

For 5 centuries: Leyv – in the 10th century, Columbus in the 15th century.
The scientific community unanimously recognizes the development of North America by the Scandinavian Vikings in the X – XI centuries. According to legend, the first European to see the shores of America was Gunnbjorn Ulfson. Eric Ryzhiy discovered Greenland in 982, having founded the first European settlement there a few years later. His son – Leif Ericsson – in 1000 reached the coast of the mainland in the Newfoundland region, calling him the land he discovered Vinland. His brother Torvald tried to establish Scandinavian settlements there, but because of enmity with the Indians, the Vikings failed to gain a foothold on the mainland.
There is a version that in the first half of the 15th century, the western shores of America from the Pacific were visited by the Chinese, led by sailor Zheng He.
You can also find very exotic and poorly verifiable theories that ancient Egypt, Ancient Rome, Mali Africans, Portuguese, Venetians, Templar knights, Scots and Irish had contact with America before Columbus.

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