What defines the horizon line in perspective drawing?

The horizon line in perspective drawing is fundamentally defined as the line that indicates where the earth's surface meets the sky. This line serves as a critical reference point in the composition of a landscape or architectural scene, providing the viewer with the sense of depth and spatial orientation. By establishing this boundary, the horizon line helps to define the viewer's eye level and facilitates the accurate representation of objects in relation to that viewpoint.

In perspective drawing, the horizon line is essential for creating a three-dimensional illusion on a two-dimensional surface. It guides the placement of vanishing points and shapes how objects recede in space, contributing significantly to the overall composition. Therefore, its role in defining the visual context of a piece is paramount and integral to effective perspective representation.