How do contour intervals function on a topographic map?

Contour intervals on a topographic map represent the vertical distance or difference in elevation between successive contour lines. Each line connects points of equal elevation, and the contour interval provides a scale for understanding the steepness and shape of the terrain. When you see closely spaced contour lines, it indicates a steep slope, while lines that are spaced further apart suggest a gentler slope.

Using this information, you can determine how much elevation changes over a certain distance, which is crucial in landscape assessment, site planning, and understanding drainage patterns. The contour interval is essential for anyone working with or interpreting topographic maps, as it translates topographical features into measurable elevation changes, allowing for more informed decision-making in design and planning processes.