Wellfleet is a town in Barnstable County, Massachusetts, United States, and is located halfway between the "tip" and "elbow" of Cape Cod. The town had a population of 2,750 at the 2010 census, which swells nearly sixfold during the summer. A total of 70% of the town's land area is under protection, and nearly half of it is part of the Cape Cod National Seashore. Wellfleet is famous for its eponymous oysters, which are celebrated in the annual October Wellfleet OysterFest.

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According to the United States Census Bureau, the town has a total area of 35.4 square miles (91.7 km2), of which 19.8 square miles (51.3 km2) is land and 15.6 square miles (40.5 km2), or 44.11%, is water.[1] Wellfleet is bordered by Truro to the north, the Atlantic Ocean to the east, Eastham to the south, and Cape Cod Bay to the west. Wellfleet is approximately 14 miles (23 km) south of Provincetown, 33 miles (53 km) (by road) northeast of Barnstable, 48 miles (77 km) from the Sagamore Bridge, and 100 miles (160 km) (by road) southeast of Boston.

The lands of Wellfleet wrap around Wellfleet Harbor, extending from the main portion of the Cape around the harbor to Jeremy Point. At one time, Wellfleet Harbor included an island known as Billingsgate Island, which sat at the harbor's mouth, to the south of the point. Once a flourishing small community with a lighthouse, the island was destroyed by coastal erosion and now exists as a shoal that is exposed at low tide. The Billingsgate shoals are split between Wellfleet and neighboring Eastham. Several other inlets extend inland from the harbor, at the mouth of the Herring River (also called "The Gut"), Duck Creek, Blackfish Creek and Fresh Brook (commonly known as "The Run") which leads to several brooks.

In addition to the Seashore, Wellfleet Bay Wildlife Sanctuary, run by Massachusetts Audubon, surrounds much of The Run, including part of Small Island (between The Run and Blackfish Creek). Between the sanctuary, seashore and other small parks and beaches, seventy percent of the town's area is protected.

A small whaling community was founded on the land that is now Wellfleet Bay Wildlife Sanctuary, and was originally known as Silver Spring, after Silver Spring Brook. What remains of it is a marsh that was once its harbor, known as the Silver Spring Brook Marshes. This land is now protected by the Massachusetts Audubon Society in its Wellfleet Bay Sanctuary.

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