There is no bank in my town.
There aren't any banks in my town.
In the first sentence we are stressing the importance of something and the idea it is not there.
In the second sentence, the importance of the bank is not stressed.
Both sentences are correct as sentences but the one above is better if you want to make a strong point.
その考え方で分かりました!
では、isn'tとの書き換えはできますか?