Perspective in Landscape Drawing
Linear perspective is an essential element of landscape drawing, especially if there are buildings, roads, fences, or power lines in your scene. When drawing on location, it's a simple matter of observing carefully and recording what you see. The effects of perspective can be subtle, and you need to be careful of the tendency to flatten planes; you know the wall is flat, so your brain tries to make you draw it that way. Remember that each set of parallel lines has its own vanishing point—so if you have a building set at a slight angle to another, its vanishing points will be different. Use a known vertical to check angles.
Even if you can't see the horizon, you can infer the location of vanishing points for parallel lines in your image. This can be useful for large areas such as hills or fields, where directional shading emphasizes perspective and can help create a feeling of space and direction in your drawing.
Atmospheric perspective, which is the apparent fading and loss of detail as objects recede, also helps establish the illusion of depth in a drawing. For example, if you have a strong, dark swath of vegetation cutting through the background of your picture, this will seem to jump forward and will appear to flatten the picture. Sometimes you can manipulate other elements accordingly—making the background darker so the vegetation recedes, for example—or you can change your handling of the problem element itself.