Plum Island

Plum Island is a barrier island located off the northeast coast of Massachusetts, north of Cape Ann, in the United States. It is approximately 11 miles in length. The island is named for the wild beach plum shrubs that grow on its dunes. It is located in parts of four municipalities in Essex County. From north to south they are the city of Newburyport, and the towns of Newbury, Rowley, and Ipswich.
Plum Island appears as an unnamed island as early as Captain John Smith's map of New England. Various scholars have speculated on the nature of the earlier accounts of European explorers in the New World, with particular focus on the latter's surveys of the coastlines of Massachusetts, but Smith's account surely identifies Plum Island. He describes a harbor at "Angoam" as having "many sands" at its entrance. Before it was an island:

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