Essex Fells is a borough in Essex County, in the U.S. state of New Jersey. As of the 2020 United States census, the borough's population was 2,244, an increase of 131 (+6.2%) from the 2010 census count of 2,113, which in turn had reflected a decline of 49 (−2.3%) from the 2,162 counted at the 2000 census.

Caldwell is a borough located in northwestern Essex County, in the U.S. state of New Jersey, about 16 miles (26 km) west of New York City and 6 miles (9.7 km) north-west of Newark, the state's most populous city. As of the 2020 United States census, the borough's population was 9,027, an increase of 1,205 (+15.4%) from the 2010 census count of 7,822, which in turn reflected an increase of 238 (+3.1%) from the 7,584 counted in the 2000 census.