“Turtle Island”
If I remember correctly today’s American Indians claim that is what the whole continent of North America is, that they believed the land was on the back of a giant turtle.
HOWEVER, Those who know more about it says the Tribes were referring to snapping turtles coming out of hibernation still with covering dirt on their backs.
The tribes would have needed a satellite to see the whole North American continent to see any turtle shape.
Not much different than the ancient Eurasian view of the world being a disk held up by elephants while standing on the back of a turtle.
Meanwhile, Eratosthenes the Greek not only knew that Earth is a globe(ish) object, but his measurement of its size and axial tilt was very close to today’s measurements.