What basic color is commonly used to indicate man-made objects on a topographic map?

The basic color typically used to represent man-made objects on a topographic map is black. This color is employed to depict a variety of human-made features, such as roads, buildings, railroads, and other structures, making it easier for users of the map to identify these elements quickly.

In topographic maps, color coding is systematically used to differentiate between natural and man-made features. While blue often represents water bodies, such as rivers and lakes, red can be used for highways or significant roads, and green generally indicates vegetation or forests. Therefore, the use of black specifically for man-made objects helps in clearly establishing what is created by human activity, allowing for better navigation and understanding of the area depicted on the map.