Cliffwood Beach is an unincorporated community and census-designated place in Aberdeen Township, Monmouth County, New Jersey, United States. As of the 2020 census, the population was 3,036. Matawan Township was incorporated on February 23, 1857. This included a portion of Middletown Point, a portion of Mt. Pleasant and Matawan beach. T…Cliffwood Beach is an unincorporated community and census-designated place in Aberdeen Township, Monmouth County, New Jersey, United States. As of the 2020 census, the population was 3,036. Matawan Township was incorporated on February 23, 1857. This included a portion of Middletown Point, a portion of Mt. Pleasant and Matawan beach. The beach area of Matawan Township would later be renamed Cliffwood Beach.