Plus, did you really think that 11th century maps are even remotely accurate? America was not even discovered (well, to most) by then.
Oh, but you think the ancient spherical earth idea is up to date and accurate, don't cha? This is what happens when you put your mouth in gear before staring the brain!
The "ancient spherical earth idea is up to date". Yes, the idea is up to date, but who ever claimed the details of their model were accurate?
If fact, at least in Western astronomy, the earth was considered stationary and the centre if the Universe until after Copernicus' time. Even then it was quite a time before the heliocentric globe was accepted widely.
Not only that, while the distance to the moon was known fairly accurately, but the distances to the (known) planets and the sun took time to determine.
So yes, the basic idea is some 2500 years, but the details have been gradually filled over time.
But Mr physical observer, you do show your ignorance by simply ridiculing what you can't understand.
Still this is what happens when you put your mouth in gear before starting the brain!
By the way, from what I can see there is still no single flat earth model that actually "works".