Complex sentence: The smallest town in New Hampshire, and the only one located entirely on islands, it is home to Fort Constitution Historic Site, Fort Stark Historic Site, and the New Castle Common, a recreation area on the Atlantic Ocean.
Split into simpler sentences: The smallest town in New Hampshire, and the only one located entirely on islands. It is home to Fort Constitution Historic Site, Fort Stark Historic Site, and the New Castle Common, a recreation area on the Atlantic Ocean.