[Robert A Cook PE]

It is postulated, but not confirmed by other evidence, that the Basque cod fishermen of North Spain and the east French coast actually were sailing to the cod fish bonanzas off of the NE and Newfoundland coastlines, but kept the location hidden for many, many years.

That said, that two Greeks wrote about a single calculation 1700 years before Columbus, does NOT mean “everybody in Europe knew the diameter of the earth had been correctly calculated”! It means ONE BOOK mentioned TWO Greeks made ONE calculation. Now, over the next 1700 years, how many OTHER PEOPLE wroteclaiming they too knew the earth was round.

Only 50 years earlier, the Portuguese began sailing south around Africa. Very, very slowly south.

[SunkenCiv]

Thanks Robert A Cook PE. The grand banks were being fished well before 1492. Gascons, Basques, people of the Low Countries, and others were expanding the fish catch to compluy with the Papal suggestion of days without meat to cover a supposed meat shortage in Europe, and the Medieval Warming period had caused fisheries to move north. It's well known that the Vikings had settlements in North America, two of them have been located, one was archaeologically excavated over 40 years ago.

Learning had taken off by Columbus' time. It's possible that the idea of a flat Earth has only caught on in quite modern times. Columbus was familiar with the ancient Greek estimate of the circumference of the Earth, but he was also familiar with the existence of a continental mass west of the Atlantic, as he'd been to Iceland to research what he'd already heard about. He also accepted another ancient Greek idea, that all the landmasses were known and were connected (other than islands), so he concluded (incorrectely) that the circumference of the Earth must be much smaller than had been accepted since classical times, and that the lands known to the Gascons, Basques, and Vikings must be the easternmost reaches of Asia.