The Layou is Dominica's longest river and has a total length of 27.6 km (17.1 mi). It runs from the island's mountainous interior into the Caribbean Sea, just south of Saint Joseph, a small fishing village on the western coast. Bamboo lines most of Layou's banks and many banana and coconut trees fill the river basin. When it is not running strong, the Layou River is excellent for swimming, but when its levels are higher, especially after rainy periods, its currents can be dangerous.

Around the river's mouth are several nice beaches. The one at Saint Joseph has black sand and is not very big. At Mero you'll find a much better one, which also includes interesting rock formations that offer good snorkeling possibilities.