Cocos Island dive sites

Bajo Alcyone is only accessible via liveaboard dive vessels departing from Puntarenas on the Pacific coast of Costa Rica. The crossing takes approximately 32-36 hours across open ocean. Trips typically run 10-12 days and include multiple dives at Bajo Alcyone along with other Cocos Island sites. Only a handful of liveaboard operators hold permits to dive Cocos, so trips sell out many months in advance.

Bajo Alcyone's unique geography as an isolated seamount creates a convergence point for currents that concentrate hammerheads in extraordinary numbers. Unlike reef wall sites where sharks pass by, at Bajo Alcyone divers kneel on the seamount at 25-35 metres and look up at a living ceiling of hundreds of hammerheads silhouetted against the surface light. The sheer density and the drama of the overhead schooling make it arguably the greatest hammerhead dive on Earth.

Bajo Alcyone is an advanced dive that demands respect but is not inherently dangerous with proper preparation. The main challenges are strong and shifting currents, depth of 30-35 metres, and the remote offshore location about 1.5 kilometres from the island. Experienced liveaboard operators know the site intimately and time dives for optimal conditions. Divers should be comfortable with deep drift diving and carry surface marker buoys.