Age of Exploration (Old Earth)
The period following the invention of open-sea navigation on Old Earth. Humanity spread out over the entire land surface of Old Earth, mostly on foot and by boat. However there was little communication between the various parts of the world before the so-called exploration age, and accurate information was difficult to come by.
A limited amount of exploration occurred in the Classical Age of the Greek and Roman Empires, but after the Medieval period deliberate exploration began in earnest. The Chinese Empire explored parts of the Pacific and Indian Ocean while the European Nations began a wide-ranging exploration effort, discovering the Americas, circumnavigating the globe and eventually mapping the whole planet.