Gruta da Camarinha

Little known among divers, Gruta da Camarinha is a crack in a huge rock of Ilha de Cabo Frio. The submerged space between the two rock masses is believed to have opened when the rocky point shifted. The wall exposes the contact of an ancient volcanic conduit, made mainly of volcanic breccia, intruded into the basement gneiss, an outcrop studied by geologists.

The cave has two entrances, one to the south and one to the east, 20 metres apart. One end of the fault lies at the back of the cove and the other opens to the sea. The crossing through the crack is done horizontally and takes 17 minutes on average. The cave lies on the outer sea, a short way past Gruta Azul, and sees little tourism. Getting there depends on calm seas.

The cliffs around Ilha do Farol show the rock erosion that gave rise to the sea caves around the island. In Arraial do Cabo it is common to come across rays, turtles and moray eels and, in rare cases, dolphins, and the region's coral fauna is well suited to macro photography.