|"Twilight Avenue", by Pascal Campion|
I'm particularly fond of this recent illustration, and have spent some time analyzing its distribution of darks and lights, the sparks of red and pink amongst all those neutrals, the illusion of wet pavement, and the use of atmospheric perspective.
There are many ways of establishing a sense of depth in a landscape. For example, figures are larger in the foreground, smaller in the background. Overlapping of shapes contributes to the effect. Distant objects have fewer details. That decorative grate on the lower left helps to situate the viewer as apart from the scene.
"Atmospheric perspective" is the use of lighter, duller colours to suggest items further away. The theory is that the further the distance, the more atmospheric particles separate the eye from the subject, lightening and dulling the distant objects. This effect is readily observed when looking at a series of distant hills.