The Ancient Greek philosophers wondered about what lay beyond places marked on their maps. Some of them tried to mathematically find answers about the unknown. When the Romans conquered, they destroyed the phenomenal library in Alexandria where much of the scolarship was happening. Neither the Romans nor the Christians (who came to power later) encouraged questioning the unknown. As a result, maps prior to 1400 A.D. were not too accurate. However, during the 1400's people did start to be curious again about what lay beyond their regions (possibly because regional rulers were gaining in power and they were less controlled by the Church). They also believed there were fortunes to be made in trading foreign goods and wanted to be the first to acquire these trade goods. Jean Fritz has done an excellent job of exploring the trips of the adventurers who started to map the world.
RL=4th-6th