Succasunna-Kenvil is a census-designated place and unincorporated area located within Roxbury Township, in Morris County, New Jersey. As of the United States 2000 Census, the CDP population was 12,569. The name of Succasunna comes from the Lenni-Lenape Native American word for Black Rock, most likely due to the rich iron-ore deposits in the area. The community was established circa 1740.