Monmouth County is located in New Jersey, within the New Jersey metropolitan area. Thanks to the county's position on the Jersey Shore and its location within commuting distance of New Jersey Cit, . Money magazine has frequently named Monmouth County as one of the 10 best areas to live in the country.Monmouth County has a total area of approximately 665 square miles of which 71% is land and 29% water. As of the 2000 census, there were 615,301 people, 224,236 households, and 160,328 families residing in Monmouth County, NJ.