Well, 500 years at least. The painting is from ~1280, and it's currently 2023, which is less than 800 years later, so Italy by definition can't have been found

Well, 500 years at least. The painting is from ~1280, and it's currently 2023, which is less than 800 years later, so Italy by definition can't have been founded 1100 years after the painting. (Can't have been... couldn't have been... can't wouldn't have been? What is the past-in-the-future perfect tense?)