What makes your city look bigger from the Map View? What makes your walls look bigger?
On the outside, your Town Hall level affects the appearance, or how big, your city looks.
Level 1 Gives you a small village.
Level 4 Gives your city some walls.
Level 7 Gives your walls towers, a gate, and increases the size of your walls.
Level 10 Makes your city extremely larger, much like a castle.
Remember, this is only about appearances from the Map View.