Christopher Klein, Illustration by McKibillo

Navigator: Boston Harbor Islands

The 34-isle archipelago, a protected national park, offers hiking, biking, and camping galore. 617-223-8666, bostonharborislands.com; ferries, 617-222-6999, harborexpress.com. History buffs love Georges Island and its Fort Warren, an old prison for Confederate soldiers. The structure’s dark passageways are refreshingly cool…