On topographic maps, certain contour lines are drawn with heavier weight and labeled with their elevation. This convention provides a quick and easy method to interpret the elevation represented by the lines. These enhanced lines, appearing at regular intervals, facilitate efficient map reading. For instance, if the contour interval is ten feet, every fifth contour line may be emphasized and annotated with its elevation above sea level. This allows map users to rapidly determine the general terrain elevation without meticulously counting each individual contour.
The practice significantly improves the readability and usability of topographic maps. By highlighting specific elevation benchmarks, the effort required for terrain analysis is considerably reduced. This is beneficial in fields such as surveying, construction, and outdoor navigation, where accurate elevation data is vital. The historical implementation of this technique reflects a dedication to clarity and efficiency in cartographic representation, promoting broader accessibility of topographic data.
