Here's a picture of the lighthouse in Edgartown, on Martha's Vinyard, Massachusetts. Edgartown is home to my great friend Alison Leslie (though she comes originally from another island of similar size, called Manhattan). If you've seen Jaws you'll know the Vineyard already, as it was filmed there - though Great Whites aren't a common pest.
Edgartown is the bit I know best, but Alison and I have cycled round most of the eastern half and cadged lifts over the rest. Great beaches, wonderful wildlife (to watch horseshoe crabs mating on the sand at your feet is a terrific experience), and a friendly community, even if a lot of them are indecently rich. Have I really not been there since 1993 - frightening thought! I wonder if Mad Martha's is still selling ice cream...