Location & Size: Guanacaste Province, between the Bebedero and Tempisque River, 30 kms west of Cañas. The National Park has 16,804 hectares.

Characteristics: Diverse flood plain habitats, bordered by rivers and a ridge of limestone hills. Between 12-15 habitats have been identified, due to the seasonal floods of great magnitude.

Fauna: 257 species of birds:herons, storks, egrets, grebes, ibis, ducks, northern jacanas and other migratory waterfowl and wading birds. Several species can be seen at Isla Pájaros (Bird Island), located inside the National Park, such as Costa Rica's largest colony of black-crowned night herons.

Mammals: Howler and white-faced monkeys, white-nosed coati, white-tailed deer, tree squirrel, porcupine and crocodiles.

Flora: Evergreen forest, deciduous forest, riparian forest, thicket forest, limestone forest, savannah woodland, mangrove swamp and saltwater marsh. The characteristic shrub is the "palo verde" or green horse bean from which the park takes its name. Also found an endemic species of cactus and the lignum-vitae, prized for its wood and in danger of extinction.

Importance of the Park: Protection of the Tempisque flooded plains, that are home to endangered species such as: the jabiru stork and the only population of scarlet macaws in the northern Pacific.

Visitor facilities: Park headquarters and trails.