where is allentown nj
Allentown, New Jersey. Allentown is a borough in Monmouth County, New Jersey, United States. As of the 2010 United States Census, the borough's population was 1,828, reflecting a decline of 54 (-2.9%) from the 1,882 counted in the 2000 Census, which had in turn increased by 54 (+3.0%) from the 1,828 counted in the 1990 Census.