The Bora Bora lagoon is a marine biologist's paradise in miniature — enclosed by a barrier reef, the water is warm (around 28°C year-round), exceptionally clear, and sheltered from ocean swells. Coral gardens cover the shallower sections of the lagoon floor, supporting an extraordinary variety of reef fish, and the deeper channels host bigger animals.
Most lagoon tours are half-day or full-day excursions by boat, combining snorkelling stops with shark and ray encounters in a sandy-bottomed area inside the reef where blacktip reef sharks and manta rays aggregate. The Coral Gardens at the northern end of the lagoon have some of the healthiest coral in French Polynesia. Scuba diving is available through several operators, with good sites for beginners and intermediates — the outside of the reef drops into a wall dive with large pelagic fish. Visibility is typically 30+ metres.