Prehistoric people had no cities and no villages; they roamed about in search of food. There were neither roads with directional signs nor maps; people could only judge by the position of the sun and the stars. For example, people living on the coast saw the sun rise from the sea and disappear behind the mountain forests in the evening, so they soon learned, that they had to face the setting sun, to get to the mountains, and that they came again to the shore, as they approached the rising sun. They watched the starry night sky and discovered constellations, wandering across the sky during the night. In the northern hemisphere, the stars moved in a circle around a fixed point, the North Star. Early humans used this star as a signpost.