Physical maps distinguish altitudes in terrain and show landscape features, such as mountains, rivers and deserts. Different colors and shades of colors represent many details about the physical landscapes. For example, shades of green lighten in color as elevation rises, and below sea level, shades of brown deepen.
Maps and physical geography have existed for thousands of years. One of the oldest found maps is a Babylonian clay engraving dating from approximately 2300 B.C. Ancient Chinese, Phoenician and Egyptian maps have also been found. Oceans, rivers and mountains are among the universal features of maps from ancient Chinese maps to modern day GPS-produced maps.