> F"or you can move to Juneau, Alaska to be sure there are no roads leaving the city"B

I was in Juneau recently, and they have some traffic. There are even a few roads that go out of town for a short distance, but by my standards, traffic is not a problem there. Lots of cars and trucks come and go via the Overseas Highway, which is Alaska's ferry system.

I give A+ ratings to the ferries in Alaska and to the buses on Oahu in Hawaii. They do public transportation right. North Carolina also has a good ferry system.
Howard