Atoll of an atoll is very small in comparison to the total area. Atoll islands are low lying, with their elevations less than 5 meters (9). Measured by total area, Lifou (1146 km²) is the largest raised coral atoll of the world, followed by Rennell Island (660 km²). More sources however list as the largest atoll in the world in terms of land area Kiritimati, which is also a raised coral atoll (321.37 km² land area; according to other sources even 575 km²), 160 km² main lagoon, 168 km² other lagoons (according to other sources 319 km² total lagoon size). The
Baa Atoll Maldives, including large mangroves and a unique diversity of fauna, such as the benthic fauna. Furthermore, the ring-shaped reef forms known as "faru" in the Dhivehi language is a reef structure which is unique to the Maldives. The southernmost uninhabited island of Olhugiri in the North Maalhosmadulu Atoll lies 13 km north of Goifulhafehendhu Atoll. Olhugiri is well known for its unique natural vegetation and for providing two of the only perching sites for the great frigatebird in the Maldives. Likewise, other marine creatures such as seaturtles and hawksbill turtles can be encountered. The Fisheries Ministry of the Maldives has