Nestled in the northeast corner of Somerset County lies the small, 2.9-square-mile borough of North Plainfield. It is bordered on the northwest by the first ridge of the Watchung Mountains and, to the south and east, the Green Brook provides a natural boundary between Union and Somerset Counties. Rock Avenue, on the west, divides North Plainfield and Green Brook. This borough, named for its proximity to the city of Plainfield, was primarily a farming community. Its growth was stimulated by the mills and quarries built along the streams that flowed through the area and by the construction of the Jersey Central Railroad in the 1850s. North Plainfield grew from 75 residents in 1832 to 4,000 by 1885. Today, approximately 19,000 people reside in this peaceful and picturesque community.