Located on the southwest coast of Terceira island, this protected area has about 3 hectares and includes a submerged cave consisting of a lava tube.

This lava tube is located in a basaltic lava flow associated with the Santa Bárbara Volcanic Complex)and presents a complex of galleries linked together, with rolled stones bottoms, boulders and sand clearings.

In this area, there are marine flora and fauna organisms, such as seaweeds and colonies of Yellow Polyp (Parazoanthus spp.), respectively.

Regarding marine fauna, also stand out the presence of Narwal Shrimp (Plesionika narval), Common Octopus (Octopus vulgaris) and many fish, such as the Swallowtail Seaperch (Anthias anthias), the Forkbeard (Phycis phycis), the Guinean Puffer (Sphoeroides marmoratus) and the Atlantic Lizardfish (Synodus saurus) and the Stingray (Dasyatis pastinaca).