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 (Indian name Mishawum) 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.

From the 1630s until the early 1800s the residential and commercial life of Charlestown was mostly focused on Boston Harbor. The Charlestown Peninsula grew into a major port community over the 18th century, and the inhabitants had little use for the rural area "beyond the neck", aside from occasional agricultural pursuits or quarrying. The completion of the 27 mile (43 km) Middlesex Canal in 1803 shifted Charlestown’s attention to its western hinterlands. The canal terminated at the Charlestown Neck, which precipitated the Neck's transition into a regional transportation hub. This would remain the case for at least another two centuries.

Although the peninsula and the mainland were technically one city, by the 1830s the rural farmers making a living "beyond the neck" had begun to resent their industrializing counterparts (and vice versa). Political separation took place in 1842, with Somerville becoming its own township. However, it was the railroads that would eventually doom the Charlestown Neck. Over the second half of the 19th century, industry would flourish throughout the region, necessitating the construction of good transportation infrastructure and reliable distribution networks. Railroads saw the Neck as a key transit point for manufactured goods produced in the Merrimack Valley, with easy access to Boston, Charlestown and Cambridge markets.

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