Portsmouth is the second largest town in Dominica, with a population of 3,630 inhabitants. Located in Saint John Parish on the north-west coast of the island, it sits on the shore of Prince Rupert Bay, a natural harbor that has historically made the settlement strategically significant. The town's name reflects its colonial history, though the area was originally called Ouyouhao by the Kalinago people and later known as Grand Anse by French settlers.
Portsmouth's geography defines much of its character. The Indian River forms the town's southern boundary, while to the north lies Cabrits National Park, situated on a peninsula that juts into Prince Rupert Bay. This natural setting has shaped both the town's development and its appeal as a destination on Dominica's northern coast.