One of the largest Harbor Islands, Peddocks consists of four headlands connected by sandbars. Hiking trails wander through marsh, pond and coastal environs, and there are campsites and yurts if you wish to spend the night. Meanwhile, the dominant feature of Peddocks Island is the remains of Fort Andrews, a large facility with more than 20 buildings. Peddocks’ proximity to the mainland ensured its use as a military stronghold, from the Revolutionary War right through to WWII.