There is a theory that the Vikings had navigated the Arctic Sea,in the 12th century which was relatively Ice free at the time and drawn maps of a northwest passage to the Bering straits. That Columbus had seen such a map and based his math on a great circle distance to that point, with no knowledge of the length of the ocean routes at the latitude of Spain. The Portuguese, had decades before reached the Azores and perhaps Labrador, which is why they might have dismissed his project.
But it was Columbus, Vespucci, Cabot, Verazzano, Hudson etc. who had at least a semi-methodical approach, the backing of nation-states and big business who finally got the New World show on the road. They also had the printing press by then, the 16th C answer to the Internet.
What always amazes me is that the strongest rigging on their ships which carried them thousands of miles, wasn't as tough as the rigging on my Thistle sailboat! To top it off, they had no real idea of where TF they were in those days, no charts and with no reliable way to fix longitude. Remember too, that we have forgotten all the explorers and colonists who never made it over ... or back.
But forget all that. Join me in celebrating Indigenous Peoples' Day, won't you? After all, their cultures of incessant intertribal warfare, followed by human sacrifices, enslavement of the conquered, cannibalism, etc should make us all celebrate them in a politically correct way, because it would cause them great loss of self-esteem to point out that they were bloody frickin' heathens. And they did give us the potato.