Glen Ridge 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 7,802, an increase of 275 from the 2010 census count of 7,527, which in turn reflected an increase of 256 from the 7,271 counted in the 2000 census. The borough is notable for being one of a few in New Jersey preservi…Glen Ridge 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 7,802, an increase of 275 from the 2010 census count of 7,527, which in turn reflected an increase of 256 from the 7,271 counted in the 2000 census. The borough is notable for being one of a few in New Jersey preserving the use of gas lamps for street lighting.