In my ongoing writing of the Kony book I dug deeply into the ancient charts used by navigators. Much of Africa was known along with the east side of Brazil and North America. Colombus used the Henricus Martellus map. Bad move. https://www.geoawesomeness.com/which-map-columbus-use/
Colombus died in 1506 but supposedly his map of the new world was found integrated into a 1513 Turkish map created by Ottoman Admiral Ahmed Muhiddin Piri. Found in the Topkapi palace in the 1920's. But wait... Antarctica? https://allthatsinteresting.com/piri-reis-map 
The first modern atlas of the known world was by compiled by Muhammad al-Idrisi, an Arab cartographer for Norman King Roger II of Sicily beginning in 1138. Although Ptolemy tried compiling Phoenician/Arab charts in the 2nd century still no North America. https://www.visualcapitalist.com/shape-of-the-world-ancient-maps/
There was still one minor problem. The Arabs, Phoenicians and others did not know how to get to America. Leif Erikson, son of Erik the Red sailed to "Vinland in 1000AD long before Columbus . So why isn't this Erikson Day? http://vinland-map.brandeis.edu/explore/historical/index.php
As a long time Fellow of the Royal Geographic Society I can encourge folks to check out the maps and books. I think they have all types of paid memberships now. https://www.rgs.org/about/our-collections/search-our-collections-(1)/
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