Ilha da Âncora is an offshore Búzios boat dive built around rocky structure, blue-water edges, and routes that can feel very different from the protected inner bays. It is usually chosen for guided scuba when sea state is settled, with schooling fish around the reef, regular turtle and ray encounters, and a more exposed open-ocean feel than the beach entries closer to town. Boat-only Búzios site with rocky structure, open-water exposure, and routes that depend heavily on swell, current, and operator judgment.