The New Jersey township that completely encircles another town

Countries & Cities · Published 15 October 2026 Swipe more like this →

In short: Monroe Township is a geographical anomaly in New Jersey. It doesn't just border other municipalities; it entirely surrounds the town of Jamesburg. This creates a rare "doughnut town" effect, where one community exists as a complete island within the borders of another.

Monroe Township, located in southern Middlesex County, serves as a primary example of a "doughnut town." This geographic phenomenon occurs when one municipality completely surrounds another. In this specific case, Monroe Township encompasses the entirety of Jamesburg, creating a unique spatial relationship between the two neighbors. This spatial arrangement makes Monroe one of only 21 such pairs in the state. It borders several other municipalities including East Windsor and Millstone Township. The township was officially incorporated by the New Jersey Legislature in 1838.

The township's scale is significant, making it the largest municipality in Middlesex County by land area. It covers approximately 42 square miles (110 km2), with a population that has seen rapid growth. Between 2000 and 2020, the population jumped from 27,999 to 48,594, a nearly 75% increase over two decades. This expansion has transformed the area from a traditional farming community into a diverse suburban hub. The area was originally a farming community before railroads arrived in the 1830s. The 2020 census marked the highest decennial population count in the township's history. Recent growth has been driven by single-family homes rather than senior developments. The township also covers 0.24 square miles of water.

While Monroe is a sprawling township, its internal layout is complex. It features numerous unincorporated communities and census-designated places, such as Rossmoor and Clearbrook, which cater to senior citizens. Despite this development, the township maintains a distinct identity, ranging from its 19th-century roots—including the only home in the township listed on the National Register of Historic Places—to its modern status as a hub for diverse religious and cultural congregations. The area is home to the largest public menorah in New Jersey. It also features a Hindu temple with the nation's largest indoor statue of Hanuman. The township's history includes a 1907 arrest of a physical culture proponent. One notable resident was the famous saxophonist Clarence Clemons.

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