This is a very vague question. Hawai`i is not only a state, it
is one of the islands that make up the state. Do you mean major
cities in the state of HI or on the island of HI?
On Hawai`i: Hilo, Kona
On O'ahu: Honolulu
On Maui: Kahului, LaHaina, Kihei
On Kuai`i: Lihue
Of course, there are others depending upon what you want.