Charlestown Neck

The Charlestown Neck was an isthmus connecting the formerly independent city of Charlestown, Massachusetts to the mainland at present-day Sullivan Square in Middlesex County. When Charlestown was first settled by British colonists it was surrounded on nearly all sides by water. Only a small strip of land called "the neck" connected what is now Charlestown to what would become Somerville.

As with Boston's founding on the Shawmut Peninsula, Charlestown was originally settled on a small peninsula accessible by land only via a small isthmus. While Charlestown was then largely separated from the mainland by an inlet of the Charles River later called Prison Point Bay, and by what was later called the Miller's River, these bodies of water have since been completely obscured by landfill and land reclamation over the late 19th and early 20th centuries.

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