Rangiroa, or "Endless Sky" in Tahitian, is French Polynesia's largest atoll. A long, narrow grouping of 415 small motu strung together in a misshapen circle, it harbors a lagoon so large the entire island of Tahiti could fit in it. It's also impossible to see from one side of the lagoon to the other.
Rangiroa's tourism industry has been built around the lagoon and the two passes (Avatoru and Tiputa) that connect it to the ocean. Divers descend on Rangi, as it's nicknamed, to "shoot the pass." The atoll's main town, Avatoru, and the village of Tiputa lie in the northern section of the atoll.