I have always thought the west end was Santa Rosa and the eastern or Fort Walton end was Okaloosa.
There may be a tiny split or two along the way.
Okaloosa/ Santa Rosa info...thanks for clearing that up. I must have lived on Okaloosa. We used to go over that bridge right by the Gulfarium to and from school everyday on the school bus. Do you know which one I mean?
The island names are the names of the counties in which they lie.