Washington is a borough in Warren County, New Jersey, United States. As of the 2010 United States Census, the borough's population was 6,461, reflecting a decline of 251 from the 6,712 counted in the 2000 Census, which had in turn increased by 238 from the 6,474 counted in the 1990 Census. The borough is located in the easternmost region of the Lehigh Valley. Washington was incorporated as a borough by an act of the New Jersey Legislature on February... Show more

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