Picture yourself creating a map of a single neighborhood on a piece of paper. Initially, you might think you should draw every street, building, sidewalk, tree, and parking lot. Before long, the map is cluttered, labels cover each other, and significant features get hidden beneath less important ones. This might have nothing to do with your drawing ability or computer mapping skills. It could be that the map’s scale does not match the quantity of information that you want to add.
The scale of a map is a description of the ratio between distance on a map and distance on Earth. A large-scale map represents a relatively small area, like a campus, a park, or a neighborhood. A small-scale map represents a larger area, like a country or a continent. The terms seem backward, because if we compare the representative fractions 1:5,000 and 1:1,000,000, the former is actually larger (one divided by five thousand is greater than one divided by one million). However, a map at a large scale like 1:5,000 can depict individual streets and buildings easily, whereas a map at a scale of 1:1,000,000 requires significant generalization.
Decide upon the purpose and scope of your map before deciding on a scale. If the map is to be used while walking around a particular neighborhood, it must contain sufficient detail to display pedestrian paths, entrances, intersections, and notable points of interest. If the map is to show several neighborhoods and cities in a region, it does not need to depict all neighborhood streets. Create one sentence that summarizes what the user should know or do when he or she views the map. Mark the full geographic extent that will fit within the map’s layout. These steps will assist you in determining what information needs space and what information can be simplified or omitted.
Try mapping the same location twice. Find a familiar area. First, create a map of the neighborhood. Second, create a map of the same area as part of a larger city. On the neighborhood map, include neighborhood streets, some building outlines, and point symbols for points of interest. On the city map, show only major streets, neighborhoods, and major points of interest. Compare the two maps. Observe the differences in symbol size, line width, label position, and level of geographic detail, even though the two maps display the same geographic area.
Scale influences the design of the legend and labels. The representation of a street on a neighborhood map is likely much larger than the representation of the same street on a city map. Buildings might have their own shape on the neighborhood map but only a single area symbol on the city map. When the extent of the map increases, it is possible that the names of places will cover other map elements, and therefore some place names might need to be abbreviated, relocated, or omitted. The scale bar should be placed in an easy-to-find location and use distance units that are appropriate for the size of the area being depicted.
During review, zoom out or print the map at the correct size. Verify that the main road network, political boundary, or thematic pattern is evident. Notice any areas where many labels and symbols vie for space. If the map can only be seen well at high levels of magnification, then the scale and detail level may be mismatched. Eliminate minor features before attempting to shrink text or make symbols too small to see.
The proper scale is not necessarily the scale that fits the whole map area on the page. It is the scale that allows the primary information in the map adequate space to convey its message. One last test to perform is to conceal the title and determine the area being shown, the important features, and the things that the user is meant to observe. When these are apparent without a search, the scale is assisting the map, not hindering it.
