<P> Topographic maps show the shape of Earth's surface by using contour lines, the lines on the map that join points of equal elevation . They are among the most well - known symbols on modern maps as they are self - explanatory and accurately represent their phenomena . They make it possible to the depict height, depth, and even slope . Contour lines will be closer together or spaced apart to show the steepness of the area . If the line is spaced closer together, it means that there is a steeper slope . If they are farther apart, the area has a low slope . An area of low slope generally uses contour intervals of 10 feet or less . Areas that contain mountain or other high slope can use an interval of 100 feet . </P> <P> Apart from showing just contour lines, topographic maps also use a lot of map symbols to represent its features . Features are represented by using point, line, and area symbols . Individual features, such as houses, are shown as point symbols like a small dot or square . However, a cluster of houses or neighborhood can be shown as a shaded area or polygon . Areas of importance or landmarks may receive special symbols that represent what they are . For instance, a church may be symbolized as a picture of a little church or cross or the town hall may have a special color or symbol . </P> <P> Many of the features will be shown by straight, curved, dashed, or solid lines . They may also be colored to represent different classes of information . The typical color standard for topographic maps depicts contours in brown, bodies of water in blue, boundaries in black, and grids and roads in red . Topographic maps may use different colors to represent area features . Most topographic maps will use green for vegetation or national parks and wildlife management areas . They will also use blue for rivers, lakes, or other bodies of water . Red may also be used to represent areas of significant importance . </P> <P> A map is a smaller representation of an area on the earth's surface; therefore, map symbols are used to represent real objects . Without symbols, maps would not be possible . Both shapes and colors can be used for symbols on maps . A small circle may mean a point of interest, with a brown circle meaning recreation, red circle meaning services, and green circle meaning rest stop . Colors may cover larger areas of a map, such as green representing forested land and blue representing waterways . To ensure that a person can correctly read a map, a map legend is a key to all the symbols used on a map . It is like a dictionary so you can understand the meaning of what the map represents / </P>

Mapmakers use single theme maps to show several attributes of the feature within the same symbol