Plum Island is a barrier island, nine miles of sand and dune lying parallel to the coast of northeastern Massachusetts, with the Atlantic on one side and a vast expanse of salt marsh on the other. Most of it is the Parker River National Wildlife Refuge, one of the best places on the East Coast to watch birds, and the road that crosses the narrow causeway from Newburyport feels like a transition from town to wilderness. On a clear day the smell of salt and marsh grass hits you before the first dune.
The marsh behind the island, the Great Marsh, is the largest continuous salt marsh in New England, and it is a breeding ground and a refuge for an enormous number of birds. Piping plovers nest on the beach in spring and early summer, and sections of the shore are closed for them, so obey the signs. In autumn, thousands of shorebirds, ducks and geese pass through, and the hedges are full of warblers. The dunes are covered in beach plum, bayberry and rosa rugosa, and in September the beach plum fruit is purple and wild. Greenhead flies, painful and persistent, are a plague in July, and the marsh is thick with mosquitoes on still evenings.
The ride itself is brief, straight and flat, and not what a rider usually seeks. The refuge road runs along the island for several miles, with a speed limit that is strictly enforced and a number of parking lots by the beach, and the whole place is limited by the number of cars it will take. On busy summer weekends the gate closes when the parking is full, so arrive early or in the shoulder seasons. The approach road from Newburyport is more fun, with salt marsh on both sides and plenty of light.
Newburyport, six kilometres away, is the town to use for everything else. It is a handsome old port with brick streets, a boardwalk along the Merrimack and a fine collection of Federal-era houses built by shipowners and captains, and it has fuel, food and everything in between. Salisbury, across the river, is more tourist-oriented. The best time on the island is October, or a calm weekday in May, when the birds are moving, the flies are absent and the light over the marsh is gold.