Advanced Costa Rica
Cocos Island
Thirty-six hours of sailing to reach the hammerhead seamounts
There's no airport, no hotel, no way to get there other than a thirty-six-hour crossing from the mainland. At the end of that crossing are seamounts with schools of hammerhead sharks among the densest on the planet.
In this profile you'll find why an uninhabited island in the eastern Pacific concentrates that many sharks, what its seamounts are like, what diving them demands, when to go, and what it means to be a national park with no permanent population.
It's one of the pillars of the Eastern Tropical Pacific Marine Corridor, the network of protected areas that migratory sharks from across the region move through.
Geography and access
Cocos Island is an uninhabited volcanic island belonging to Costa Rica, located about five hundred and fifty kilometers from the mainland, in the eastern tropical Pacific.
It's an oceanic island: it has no continental shelf. The walls drop from the surface to very deep bottoms, and around it there are seamounts that rise from the blue without ever breaking the surface.
Those seamounts are the key point. They intercept nutrient-laden currents and function as cleaning stations and meeting points for migratory sharks that travel thousands of kilometers.
The island is part of the marine corridor connecting Galápagos, Malpelo, Coiba, and this island: the same individual hammerhead sharks have been recorded moving between them.
Access is exclusively by liveaboard from the Costa Rican Pacific, with a crossing of about thirty-six hours each way. There's no accommodation on land and no shore diving.
The national park limits the number of vessels, requires permits, and prohibits landing outside authorized points.
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