Marieta Islands Hidden Beach

The Marieta Islands are a small uninhabited archipelago approximately 35 kilometers offshore from Puerto Vallarta in Nayarit state, protected as a national park and UNESCO Biosphere Reserve. The islands were formed through volcanic activity and further shaped by early 20th-century military artillery testing, which created unusual geological formations including sea caves and a collapsed volcanic crater whose ocean-facing wall opened to reveal a sheltered beach entirely enclosed within the island — universally known as Playa Escondida or the Hidden Beach. This beach is accessible only by swimming through a natural rock tunnel approximately 10 to 15 meters long from the adjacent cove, passable only at certain tidal windows. The tunnel requires swimming in open water and comfort with low overhead clearance for a brief moment. Beyond the hidden beach itself, the waters surrounding the Marieta Islands support exceptional snorkeling and diving — manta rays, sea turtles, reef fish, octopus, and seasonal humpback whale sightings between December and March are all regularly reported. Blue-footed booby birds nest on the rocky island surfaces and are visible from touring boats throughout the year. To protect the fragile ecosystem, the national park authority limits access to a maximum of 116 visitors per day to the hidden beach zone, creating a booking bottleneck that requires advance reservation weeks or months ahead during peak season. Only tour operators certified by the national park authority are permitted to bring visitors to Playa Escondida — independent kayak or boat access to the hidden beach is prohibited. Tours depart from marinas in Puerto Vallarta and Punta de Mita.