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Middlesex County, New Jersey

County in New Jersey, United States

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Through Culture and Headquarters

The county is located in the middle of the Northeast megalopolis of the U.S. The county's most populous place, with 107,588 residents as of the 2020 census, is Edison, while Monroe Township covers the largest area of any municipality, at 42.19 square miles (109.3 km2). Since the 2010 census, the state's center of population is in East Brunswick; the center of population for New Jersey has been in Middlesex County since the 1900 census. Middlesex County hosts an extensive transportation network, including several rail stations along the heavily traveled Northeast Corridor Line of the New Jersey Transit commuter rail system, as well as the intersection of the New Jersey Turnpike and the Garden State Parkway, the state's two busiest motor vehicle roadways, in Woodbridge Township. Many towns within Middlesex County serve as commuter towns to New York City, as well as to employment centers in Jersey City, Newark, and other points in North Jersey.

The county was primarily settled due to its optimal location along the Raritan River. Middlesex was originally formed as one of four administrative districts within Province of East Jersey in 1675, together with Bergen, Essex and Monmouth districts. Middlesex County was formed within East Jersey on March 7, 1683. The population increased so the county was partitioned on October 31, 1693, into the townships of Piscataway, Perth Amboy, and Woodbridge. Adjacent Somerset County was established on May 14, 1688, created from portions of Middlesex County.

The county's first court met in June 1683 in Piscataway, and held session at alternating sites over the next century in Perth Amboy, Piscataway, and Woodbridge before relocating permanently to New Brunswick in 1778. Despite its status as a residential, commercial, and industrial stronghold and a centrally accessible transportation hub, Middlesex is also home to an extensive public park system with expansive greenways, totaling more than 6,300 acres (2,500 ha). Middlesex County is most demographically notable as the U.S. county with the highest concentration of Asian Indians, at nearly 20% in 2020, spanning the county's boundaries between Little India, Edison/Iselin in the north and Monroe Township at its southern tip.

Geography and climate

Middlesex has a hot-summer humid continental climate (Dfa) which borders a humid subtropical climate (Cfa) on Raritan Bay and Arthur Kill. Average monthly temperatures in downtown New Brunswick range from 31.9 °F (−0.1 °C) in January to 75.6 °F (24.2 °C) in July, while in South Amboy they range from 32.3 °F (0.2 °C) in January to 75.9 °F (24.4 °C) in July. In recent years, average temperatures in the county seat of New Brunswick have ranged from a low of 22 °F (−6 °C) in January to a high of 86 °F (30 °C) in July, although a record low of −13 °F (−25 °C) was recorded in January 1984 and a record high of 103 °F (39 °C) was recorded in July 1999. Average monthly precipitation ranged from 2.98 inches (76 mm) in February to 5.08 inches (129 mm) in July.

According to the U.S. Census Bureau, as of the 2020 Census, the county had a total area of 322.87 square miles (836.2 km2), of which 309.22 square miles (800.9 km2) was land (95.8%) and 13.65 square miles (35.4 km2) was water (4.2%). The county is named after the historic English county of Middlesex.

Bisected by the Raritan River, the county is topographically typical of Central Jersey in that it is largely flat. The majority of the county is located on the inner coastal plain, with the remainder of the county being located on the Eastern Piedmont. The elevation ranges from sea level to 300 feet (91 m) above sea level on a hill scaled by Major Road/ Sand Hill Road near Route 1 in South Brunswick Township.

Another area with higher elevation in the county is the Perth Amboy Moraine, left by the southern limit of the Laurentide Ice Sheet. Only the far northeastern area of the county was glaciated, and the Perth Amboy Moraine stretches from Perth Amboy, through Woodbridge, Edison and Metutchen, and stradles the border of Edison and South Plainfield before exiting the county. The area includes peaks of over 200 feet.

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