One of the things I love so much about these early maps is that they weren't just directions from Point A to Point B. The maps themselves were intricately illustrated and often reflected the worldview of the time. I love this Ebstorf map.
This kind of map is called a mappa mundi, which is a medieval map of the world. This one was made on a number of stitched together goatskins. I am especially fond of the detail at the top and bottom of the map, (warning: large image!) as well as the left and right sides. You can see the head and feet and hands of God as he holds up the world--a reflection of the science of the time.