What is NOT one of the terrain features of a map?

The correct answer is that a plain is not categorized as a specific terrain feature on a map. In the context of mapping, terrain features typically refer to distinguishable and defined elevations or depressions in the landscape, such as hills, valleys, and depressions.

Hills represent raised areas of land and are important for identifying higher ground, which can be critical for navigation and strategic planning. Valleys indicate lower areas between hills or mountains, often serving as routes for waterways or pathways. Depressions are areas lower than the surrounding terrain and can influence local drainage patterns.

In contrast, a plain is generally considered a large, flat area of land with little change in elevation and lacks distinctive features that separate it from surrounding terrain. While plains do exist and are important geographical features, they do not fit within the same framework as the more defined or notable features like hills, valleys, and depressions that are actively used in military and navigational contexts. Thus, identifying a plain as a terrain feature on a map doesn’t align with how specific terrain elevations and depressions are categorized.