What do closely spaced contour lines on a map indicate?

Closely spaced contour lines on a map indicate a steep slope. This is because contour lines connect points of equal elevation on a topographic map. When these lines are close together, it signifies that there is a rapid change in elevation over a short horizontal distance, which reflects a steep incline or decline in the terrain. This can be particularly important in land navigation, as steep slopes can affect both route selection and the difficulty of traversing an area.

On the other hand, flat surfaces are represented by widely spaced contour lines, as there is little change in elevation across that area. A river course would typically not be indicated by contour lines, as they represent ground elevation rather than water flow. Lastly, the presence of dense forest does not directly correlate with contour line spacing, as it pertains more to vegetation cover rather than changes in elevation. Thus, the correct interpretation of closely spaced contour lines is that they indicate a steep slope.