It is the southernmost point of geopolitical North America if non-continental islands are included, and the only landmass above water on the Cocos tectonic plate.

[6] Surrounded by deep waters with counter-currents, Cocos Island is admired by scuba divers for its populations of hammerhead sharks, rays, dolphins and other large marine species.

[9] Cocos Island was declared a Costa Rican National Park by means of an executive decree in 1978 and designated a World Heritage Site by UNESCO in 1997.

For many, the main attractions are the large pelagic fish species, which are very abundant in this unique meeting point between deep and shallow waters.

Such accolades have highlighted the urgent need to protect Cocos Island and its surrounding waters from illegal large-scale fishing, poaching and other threats.

The only persons allowed to live on Cocos Island are Costa Rican park rangers, who have established two encampments, including one at English Bay.

Some small caches have been discovered,[citation needed] leading many to believe that the stories of vast pirate treasures are true, though the majority of searches have been unsuccessful.

Potassium–argon dating established the age of the oldest rocks between 1.91 and 2.44 million years[19] and it is composed primarily of basalt, which is formed by cooling lava.

[19] In spite of its mountainous character, there are flatter areas between 200–260 m (660–850 ft) in elevation in the center of the island, which are said to be a transitional stage of the geomorphological cycle of V-shaped valleys.

[22] Cocos Island has a number of short rivers and streams that drain abundant rainfall into four bays, three of them on the north side (Wafer, Chatham and Weston).

Sheer, 90-metre (300 ft) cliffs ring much of the island, preventing convenient access except at a few beaches; the easiest point of entry is at Chatham Bay.

The climate of Cocos Island is mostly determined by the latitudinal movement of the Intertropical Convergence Zone, which creates cloudiness and precipitation that is constant throughout the year.

"Palo de hierro" or huriki (Sacoglottis holdridgei), "avocado" (Ocotea insularis) and the endemic Cecropia pittieri are the most common canopy trees.

Heyerdahl theorized that these plantations were used to provide fresh liquid and food for pre-Columbian voyages (made by balsa rafts using guara navigation) between Guatemala and northwestern South America.

After the Spanish conquest and its consequences, these voyages ended and the tropical jungle recovered the land that had been laboriously cleared by early human hands.

[36] The island has no native land mammal species, but humans have introduced five: pigs, deer, goats, cats, and rats.

[42] Growing local and worldwide demand for tuna, shark fin soup and other seafood is threatening the island's fragile ecosystems.

[43] The government of Costa Rica has been openly accused of passivity and even benefiting corruptly from illegal shark fin and other seafood trade to large markets, such as China and other Asian countries.

[45] However, efforts to effectively patrol the waters and enforce environmental laws face big financial and bureaucratic difficulties, as well as being prone to the corruption of local, national and international authorities.

Marvin Orlando Cerdas, a judge with the local Puntarenas Court of Justice, obscurely allowed 22 poachers caught red-handed to escape the country.

[48] Also under highly suspicious and allegedly corrupt circumstances, District Attorney Michael Morales Molina stopped the auction for public benefit of confiscated goods immediately after the spokesman of the large illegal poaching ship Tiuna simply made the request.

[54] D. Lievre, Una isla desierta en el Pacífico; la isla del Coco in Los viajes de Cockburn y Lievre por Costa Rica (1962: 134) tells that the first document with the name "Isle de Coques" is a map painted on parchment, called that of Henry II, that appeared in 1542 during the reign of Francis I of France.

Willem Blaeu's Grand Atlas, originally published in 1662, has a colour world map on the back of its front cover which shows I. de Cocos right on the Equator.

Emanuel Bowen, in A Complete system of Geography, Volume II (London, 1747: 586), states that the Galápagos islands stretch 5 degrees north of the Equator.

Dampier writes: 'The Island Cocos is so named by the Spaniards, because there are abundances of Coco-Nut Trees growing on it'...prehistoric planters must have found the location of Cocos Island worthy of the vast amount of labor spent in clearing the natural jungle for the planting of coconuts...make it an ideal port of call for aboriginal merchants trafficking the open sea off Panama.

Whalers stopped regularly at Cocos Island until the mid-19th century, when inexpensive kerosene started to replace whale oil for lighting.

In October 1863, the ship Adelante marooned 426 Tongan former slaves on the island when it was discovered that they had contracted smallpox and were a danger to her crew.

In 1897, the Costa Rican government named the German adventurer and treasure hunter August Gissler the first Governor of Cocos Island and allowed him to establish a short-lived colony there.

[59] Another pirate supposed to have buried treasure on the island was the Portuguese Benito Bonito, who began terrorizing the west coast of the Americas around 1818.

Instead of waiting in the harbor as they were instructed,[63] Thompson and his crew killed the viceroy's men and sailed to Cocos, where they allegedly buried the treasure.