Located in the Pacific Ocean in front of Corcovado National Park, in the Peninsula Osa. Approximately 15-km deep sea of the San Pedrillo place established by means of the Law No.6215, of March 9, 1978, has an extension of 200 hectares in the land part and 2.700 hectares in the sea part.
The island has archeological importance, due in pre columbine time was used as a native cemetery. The cultural materials are ceramic remainders and handicraft, including the typical Diquis spheres. The most abundant ceramic correspond to the Good Waters Phase (220-800A.C), and Chiriqui (1.000-1.550 A.C). The presence of ceramic remainders of the Middle Policromo of Guanacaste Period, suggest the island was an important place for the commercial exchange a long the Pacific coast.
Also for protect wild life and flora species characteristic of the tropical rainy forest and important sea environments.
The island is cover by an always-green tropical rainy forest, with approximate 158 superior plants and ferns species. You can found trees of 50 mts tall where you can notice the thick Vaco tree, also the one called Milk Tree because it has a white liquid you can drink. Other trees species common in this place are the guapinol, higuerón, the wild cacao , the rubber and garumo, where bromelias and orchids grow.
Also in the island you can observe ferns, heliconias, bejucos and some other species like the mango, oranges, guayabo and bananas.
The wild life is very little. The birds are represented by about 10 species, the most common the garza del ganado, the gavilán cangrejero, the eagle fish and the piquero moreno. About the mammals you can observe the four eyes fox, the tepezcuintle, some rats species and several bats. Also small snakes, the boa, frogs and lizards.
The island protects very important sea environments, where the choral reef is noticed due to its extension and species. Associate with the reef you can found a great diversity of fish, invertebrates, seaweed and mammals like the dolphins and whales. The sea species are located in different environments like the choral reef, rocky beaches where a lot of fish, sea stars, porcupines, lobsters and cambutes live. The last two are en danger of extinct.