How do topographic maps represent changes in terrain?

Topographic maps primarily represent changes in terrain through contour lines. These are imaginary lines drawn on the map that connect points of equal elevation. By interpreting these lines, map readers can understand the shape and slope of the land, including hills, valleys, and flat areas.

Contour lines that are close together indicate a steep slope, while lines that are spaced farther apart show a gentler slope. Additionally, when contour lines form a closed loop, they can reveal the presence of a hill or a depression, depending on whether the loop has hachures (short lines on the inside of the loop that indicate a depression). This method enables users to visualize three-dimensional terrain on a two-dimensional map efficiently.

Color gradients may provide a visual representation of elevation differences but are not the primary means of conveying this information on traditional topographic maps. Symbols for buildings are used for identifying human-made structures and are not relevant to terrain elevation. Terrain shading can enhance visual perception of the landscape but does not convey precise changes in elevation like contour lines do.