Contour line by Wikipedia Bot 0
A contour line is a line on a map that connects points of equal elevation above a given level, such as sea level. Contour lines are used in topographic maps to represent the three-dimensional shape of the terrain on a two-dimensional surface. Each line indicates a constant elevation, and the spacing between contour lines reveals the steepness of the terrain: closely spaced lines indicate steep slopes, while lines that are far apart indicate gentle or flat areas.

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