How does contour line spacing relate to the slope of the terrain?

How does contour line spacing relate to the slope of the terrain?

• A. Widely spaced lines indicate steeper terrain.
• B. Line spacing indicates distance between points.
• C. Closely spaced lines indicate steeper terrain.
• D. Line spacing indicates vegetation density.

Answer: (C)

Contour lines mark points at the same elevation, and the spacing between them reflects how quickly elevation changes over a distance. Because the vertical step between adjacent lines is fixed by the map’s contour interval, lines that are close together mean you gain elevation quickly in a short horizontal distance, i.e., a steep slope. When the elevation change occurs over a longer horizontal distance, the lines are spread out, indicating a gentler slope. This is why a steep hillside shows tightly packed lines, while a flat or gently sloping area shows widely spaced lines. The line spacing specifically conveys slope, not vegetation or the distance between points.

Contour lines mark points at the same elevation, and the spacing between them reflects how quickly elevation changes over a distance. Because the vertical step between adjacent lines is fixed by the map’s contour interval, lines that are close together mean you gain elevation quickly in a short horizontal distance, i.e., a steep slope. When the elevation change occurs over a longer horizontal distance, the lines are spread out, indicating a gentler slope. This is why a steep hillside shows tightly packed lines, while a flat or gently sloping area shows widely spaced lines. The line spacing specifically conveys slope, not vegetation or the distance between points.