Plum Island (Massachusetts)

Plum Island
Sand dunes on Plum Island, Massachusetts.
Sand dunes on Plum Island, Massachusetts.
Location of Plum Island in northeastern Massachusetts
Location of Plum Island in northeastern Massachusetts
Plum Island
Location of Plum Island in northeastern Massachusetts.
Location of Plum Island in northeastern Massachusetts
Location of Plum Island in northeastern Massachusetts
Plum Island
Plum Island (the United States)
EtymologyNamed for the preponderance of beach plum thickets on the island.
Geography
LocationAtlantic Ocean
Coordinates42°45′15″N 70°47′51″W / 42.7542°N 70.7975°W / 42.7542; -70.7975
Length11 mi (18 km)
Highest pointSand dunes can reach 50 ft (15 m) in height above sea level
Administration
StateMassachusetts Massachusetts
CountyEssex
Towns and CitiesNewburyport (city), Newbury (town), Rowley (town), and Ipswich, Massachusetts (town)
Additional information
Time zone
 • Summer (DST)
Sand dunes in 1908
South Beach
Sunset at Newbury Beach in 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 (18 km) in length. The island is named for the wild beach plum shrubs that grow on its dunes, but is also famous for the purple sands at high tide, which get their color from tiny crystals of pink pyrope garnet. 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.