It is Colombia's only underwater park, and one of three
national parks in the Colombian Caribbean with coral reefs on its territories, the other two being
Tayrona and
Old Providence McBean Lagoon. It was established in 1977 to protect the coral reef on one of the islands in the
Islas del Rosario archipelago, originally extending . In 1988, an area of was incorporated, and finally in 1996 the park was expanded to the present area, , including
Archipelago of San Bernardo. The park is molded by the Caribbean and Panama currents, as well as freshwater from the
Canal del Dique. Sediments brought from
Magdalena River by the channel is having a negative effect of the park, as it deteriorates the reef. There are no bodies of freshwater in the park, but there is
brackish water in some of the
lagoons on the islands. Average yearly temperature is 27–30 °C. ==Flora and fauna==