Sandyston Township is a small rural township in Sussex County, in the U.S. state of New Jersey. It is located in the northwestern part of the state near the Pennsylvania border. The township is surrounded by and part of many national and state parks. As of the 2020 United States census, the township's population was 1,977, a decrease of 21 (−1.1%) from the 2010 census count of 1,998, which in turn reflected an increase of 173 (+9.5%) from the 1,825 counted in the 2000 census. Sandyston's growth in recent years has been attributed to the influx of people from more urban parts of the state and even New York City, located less than 75 miles (121 km) away.

Walpack Township is a township in Sussex County, in the U.S. state of New Jersey. As of the 2020 United States census, the township's population was 7, a decrease of 9 (−56.3%) from the 2010 census count of 16, which in turn reflected a decline of 34 (−82.9%) from the 41 counted in the 2000 census. Walpack Township was the smallest municipality by population and one of only four municipalities in New Jersey with a population under 100 as of the 2020 Census; it had the state's third-smallest population in the 2010 census, behind Tavistock and the now-defunct Pine Valley, both in Camden County.