Im going to tell what is so unique about chicago pizza. I think it's because chicago has the best pizza, it has more toppings bread and crust is better people like chicago pizza better then any other pizza.
Old Chicago style pizza is generally much thicker than most other pizza. It is almost a deep dish style pizza. Other than that, most other characteristics are the same: cheese, tomatoe sauce, toppings.
Chicago pizza is unique because it is deep dish in style. The original Pizzeria Uno's is in Chicago and if you are ever there, it is worth stopping in.
