The illusion of having your layout seem like more than one city can be easily done using scenic dividers. They prevent the viewer from seeing the whole train at one time, or looking like a dog chasing its tail. By operating the layout with scenic hardboard, you can have different towns on each side, or even different regions all together. Placing a city scene with a power plant on one side, while having a mountainous area with a coal mine on the other side, is an easy way to make your layout seem larger than it is.
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