 Adjacent to the East Somerville area of Somerville, Sullivan Square is named after James Sullivan, an early 19th-century Governor of Massachusetts.In the early 2000s, the Sullivan Square Overpass was dismantled, which left a stub approach to Route 99.Sullivan Square stands on what was once a narrow neck of land referred to as the Charlestown Neck, an area that was originally a thin strip of land connecting the Charlestown Peninsula with present-day East Somerville.