Which Island is in the Town of Southold in Suffolk County, New York in the United States Plum Island or Block Island Sound?
Block Island Sound: Block Island Sound is a strait in the open Atlantic Ocean, approximately 10 mi wide, separating Block Island from the coast of mainland Rhode Island in the United States. Plum Island (New York): Plum Island is an island in the Town of Southold in Suffolk County, New York in the United States.
Plum Island