This is one of the most beautiful wilderness areas in the country. It has 5,013 hectares in the land portion and 4,436 hectares of sea floor, and is found in the SE corner of the country, near the border with Panama. The coast consists of coral rock points and fantastic white sand beaches. The refuge contains the coral reefs that lie off Uva, Manzanillo and Mona Points. These reefs cover more than 5 square kilometers.
 The largest part of the terrestrial part of the refuge is covered with forest while the remainder is grassland and cultivated fields. South of Mona Point there is a 400 hectare swamp with mostly holillo and sajo palms ( Raphia taedigera and Campnosperma panamensis). The Gandoca Estuary lies in the SE of the refuge and contains mostly red mangrove (Rhizophora mangle). Not only is this a tarpon spawning ground but holds a concentration of the manatee.