In topographic maps, what is indicated by brown lines?

Brown lines on topographic maps represent contour lines, which indicate elevation changes in the terrain. Each contour line connects points of equal elevation, helping users visualize the landscape's shape, such as hills, valleys, and slopes. The spacing of these lines provides information about the steepness of the terrain; closely spaced lines suggest a steep slope, while widely spaced lines indicate a gentle slope.

Contour intervals detail the vertical distance between each contour line, allowing users to determine changes in elevation across a given area. Understanding these features is essential for navigation, planning excursions, or conducting search and rescue operations in varied terrains. In contrast, other colors and symbols on the map signify different geographic features, such as water bodies or infrastructure, providing comprehensive information about the area for better situational awareness.