Palo Verde National Park is one of Central America's largest protected wildlife areas covering 18,417-hectares (45,000-acres) of wetland in the incredibly dry province of Nicoya. In Palo Verde, the traveler will find marshes, evergreen forests, grassy savannahs, woodlands and mangrove swamps. The major rivers of the region drain into two basins and there are lagoons. Combined, these sources of water offer rich habitat for wildlife.

Named for the green tree (palo verde) Palo Verde National Park is filled with this small shrub that is green all year round. Palo Verde is part of a larger preservation area and joins onto a wildlife refuge, a reserve and Barra Honda National Park to form a mega conservation park.

There are 300 different species of birds including waterfowl and shorebirds in this park. The waterfowl migrate through this sanctuary. Frequently sighted birds include the herons, storks, spoonbills, egrets, ibis, grebes, anhingas, ducks, scarlet macaws, curassows, toucans, and parrots.

Mammals sighted in Palo Verde National Park include monkeys, armadillos, peccaries, jaguarondi, deer, and coatis.

There are numerous reptiles including crocodiles including some as long as 5m (16 ft). Iguanas are also found in Palo Verde.

From Palo Verde National Park, it is possible to charter a boat or hire a guide.

Barra Honda National Park adjacent to Palo Verde National Park and is located in the Nicoya Peninsula of Costa Rica. Barra Honda is unique because it's a cave system where pre-Columbian remains have been discovered.

There are local guides who can take you to explore this underground national park. There's also opportunities for other activities such as hiking, wildlife and bird viewing.