Man explored the world long before the days of Columbus and Magellan. Even in the earliest moments of human history, when the known world was little more than what extended within sight, there were men who were sent out to explore the unknown.
When the first explorers set out into unknown parts of the world, they had no way of being prepared for what they saw. They saw parts of the world that were completely unlike anything they had ever imagined. Then, they had to come home and try to find a way to put the things they had seen into words.