What is the primary attribute of 'Cliff' as a terrain feature?

The primary attribute of 'Cliff' as a terrain feature is a steep drop-off. Cliffs are characterized by their vertical or near-vertical walls that create a significant elevation change over a short horizontal distance. This distinctive feature affects various aspects of navigation, visibility, and military operations, as cliffs can serve as natural barriers, defensive positions, or obstacles to movement.

Understanding cliffs is crucial for tactical planning, as they can influence how forces maneuver or how the enemy may be positioned. Gentle slopes, flat land, and water sources, while important terrain features in their own right, do not describe the unique characteristics of cliffs, which are primarily defined by their dramatic elevation changes and steepness.