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.

Roseland is a borough in western Essex County, in the U.S. state of New Jersey. As of the 2020 United States census, the borough's population was 6,299, an increase of 480 (+8.2%) from the 2010 census count of 5,819, which in turn reflected an increase of 521 (+9.8%) from the 5,298 counted in the 2000 census.