Topographic Maps

1. Topographic Maps The surface of the Earth is covered with landforms such as hills, valleys, cliffs, or canyons. It is important to know where these features are when planning where to build roads, buildings and other structures. Although most maps show rivers, roads and towns in an area, they don’t show the landforms. A topographic mapuses a series of lines to represent the three-dimensional shape of the land surface. Each line called a contour line, represents a specific elevation above sea level. For example, one contour line on a topographic map might represent all the points on the map having an elevation of 100 meters above sea level. The contour intervalis the change in elevation between adjacent contour lines. For example, if there is a 100 meter contour line right next to a 110 meter contour line, the contour interval is 10 meters.