I’ve been asked a lot about how to depict different scales recently. The question is – how do you tell the viewer of one map that they’re looking at a zoomed in region of a small area, and on another map convince the viewer that they’re looking at a large area, zoomed out. The easiest cue for the viewer is mountain ranges. These are the feature that’s different enough at different scales that they can act as a defacto scale-bar.