General Discussion

The belief that educated people during the Middle Ages thought the Earth was flat. 5th century Greece is the earliest written proof that the Earth was a sphere. In 240 BC Eratosthene calculated the circumference. Early Middle Ages, 600 to 1000 AD educated people from Europe and the Middle East knew the Earth was round. And was nonexistant from Late Middle Age onwards. There never was a period of flat Earth darkness. No educated people in history of Western Civilization from 3rd century BC onward believed the Earth to be flat. Flat Earth came about between 1870 and 1920 over struggles with biological evolution.
Exception to this myth is the Great A'tuin, a world turtle with 4 immense elephants
Berilia, Tubul, Great T'Phon and Jerakeen stand on it's shell and discworld rests on their shoulders. My favorite author Terry Pratchett's Discworld series.