Penns Grove is a borough in Salem County, in the U.S. state of New Jersey. As of the 2020 United States census, the borough's population was 4,837, a decrease of 310 (−6.0%) from the 2010 census count of 5,147, which in turn reflected an increase of 261 (+5.3%) from the 4,886 counted in the 2000 census.

Route 48 is an east–west state highway in Salem County in the U.S. state of New Jersey. It is a 4.26-mile (6.86 km) route running from U.S. Route 130 and County Route 675 in Penns Grove southeast to US 40 in Carneys Point Township. It is known as East Main Street from US 130 to DuPont Road, and as the Harding Highway from DuPont Road to its terminus at US 40. Route 48 is signed east–west, although it travels more northwest-southeast throughout its route. It is a two-lane, undivided road through its entire length that intersects with Interstate 295 (I-295) and CR 551.