Well, just about any beach is cool. Depends, do you want to swim and sun worship or go for the scenic, historic stuff? We went to Martha's Vineyard last year. It's for the old timey salt of the sea, picturesque historic type of vacation, in my opinion. You have to ride the
Marthas Vineyard ferry to get there, or fly, no other choices, well, swim I guess. Wouldn't recommend that.