Seabrook is a town in Rockingham County, New Hampshire, United States. Located at the southern end of the coast of New Hampshire on the border with Massachusetts, Seabrook is noted as the location of the Seabrook Nuclear Power Station, the third-most recently constructed nuclear power plant in the United States. According to the United States Census Bureau, the town has a total area of 9.6 square miles (25 Square Kilometer), of which 8.9 sq mi (23 Square Kilometer) is land and 0.8 sq mi (2.1 Square Kilometer) is water, comprising 7.8% of the town. Directly south of Seabrook is the town of Salisbury, Massachusetts, while directly north are the town of Hampton Falls and the resort community of Hampton Beach. The census-designated place of Seabrook Beach occupies the eastern end of the town, along the Atlantic Ocean. The highest point in Seabrook is 217 feet (66 m) above sea level on Grape Hill, whose 230-foot (70 m) summit lies just south of the town line in Salisbury, Massachusetts.