Traveling by train, you see the backsides of a lot of cities. Warehouses. Highway overpasses. Housing developments. Industrial parks. Cheap houses. Porn shops with desolate parking lots. Trains run on the land that no one wants to use for anything else.
And of course, traveling at night through those wide spaces between the cities – they exist, even on the Eastern Seaboard – there are long stretches where you see nothing but black.