Travel Glossary · Islands & Resorts
Atoll
Definition
Atoll: An atoll is a ring-shaped coral reef or chain of islets encircling a lagoon, formed where a volcanic island has subsided beneath the sea.
Atolls begin as fringing reefs around a volcanic island. Over millions of years the island slowly sinks while the coral keeps growing upward, until only the reef and its islets remain around a central lagoon. Charles Darwin proposed this explanation in the 1830s. Bora Bora, a high island with a wide barrier reef, shows the process partway along.
French Polynesia’s Tuamotu Archipelago holds dozens of atolls. Rangiroa is among the largest atolls on Earth, and Fakarava is part of a UNESCO Biosphere Reserve. Their passes, the channels where ocean water flows in and out of the lagoon, are famous for diving with sharks, rays, and dolphins. The word itself comes from the Maldives, a nation of atolls.
Atolls are flat and quiet, with no mountains, few roads, and a slower pace. They pair well with a high island like Bora Bora or Moorea on an island-hopping itinerary.
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Go deeper
- French PolynesiaRangiroa Atoll GuidePlan Rangiroa, one of the world’s largest atolls: Tiputa Pass dolphins and drift dives, the Blue Lagoon, where to stay and how to pair it with Bora Bora.
- French PolynesiaFakarava Atoll GuidePlan Fakarava, a UNESCO biosphere reserve atoll: the south pass wall of sharks, Garuae Pass drift dives, family pensions and the best time to go for divers.
- French PolynesiaTikehau Atoll GuidePlan Tikehau, a small Tuamotu atoll of pink-sand beaches and bird islands: how to get there, where to stay, what to do and how to pair it with Rangiroa.
- DestinationsMaldives, MaldivesOne overwater villa, zero itinerary. The trip you don't plan a second day for.
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