Currently, when I have used code to add a city or district within a state, to Woocommerce, these cities and districts appears as an additional state in a country, not as city or district under the state they are located. For example, Ikeja is a district/capital of Lagos State in Nigeria. But when code is used to add it (Ikeja) to Woocommerce shipping zone, it appears as a new state under Nigeria thus, Ikeja, Nigeria becomes a new state and appears as such in checkout page drop-down.

When LA, Sacramento, San Diego and San Francisco are added to Woocommerce Shipping Zone using code, they appear as additional states in the United States not as cities under California. Increasing the states in the USA beyond the 50 mark.

On some forums, postcode have been mentioned, but not all countries listed in Woocommerce core have a functional postcode. And there are times postcode in some countries like mine, covers an area the size of Johannesburg and Pretoria put together, especially remote areas. It is easier for most people to acquainted with the names cities and districts they live than postcodes.

So the ability to breakdown the Woocommerce core beyond it present structure of state/province/region of a country to include placement for cities and districts under such states would simplify and greatly aid shipping.