Northern New Jersey

North Jersey comprises the northern portions of the U.S. state of New Jersey between the upper Delaware River and the Atlantic Ocean. The designation of northern New Jersey with a distinct toponym is a colloquial one rather than an administrative one, reflecting not only geographical but also perceived cultural differences from the southern part of the state, with no official definition.

Geologically, the north is in the Piedmont Province, the Highlands Province, and the Ridge and Valley Province. Depending on definitions, some is counted as being in the Atlantic coastal plain.

A broad definition includes all points in New Jersey north of I-295 in the western part of the state and all points north of I-195 in the eastern part of the state. Another definition uses the 1958 telephone area code 201 (not the modern area), and all its additions. Some people, especially residents of the northern tier of counties, use a narrower definition, counting only that area north of the mouth of the Raritan River.

The state is also sometimes described as having North Jersey and South Jersey separated from each other by Central Jersey.

Generally in this approach, North Jersey is defined as anything north of a line extending from I-287 in Edison westward to US 22 and I-78. South of that line down to I-195 is referred to as Central Jersey, and anything south of I-195 is South Jersey.

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