Atoll remains of an ancient atoll as a hill in a limestone area is called a reef knoll. The second largest atoll by dry land area is Aldabra with 155 km². The largest atoll in terms of island numbers is Huvadhu Atoll in the south of the Maldives with 255 islands. In 1842, Charles Darwin explained the creation of coral atolls in the southern Pacific Ocean based upon observations made during a five-year voyage aboard from 1831 to 1836. Accepted as basically correct, his explanation involved considering that several tropical island types—from high volcanic island, through barrier reef island, to atoll—represented
Haa Alif Atoll uninhabited islands in Haa Alif Atoll are under the control of the North Thiladhunmathi Atoll Council. Resort Islands Other Uninhabited Islands These are islands which during recorded history, have been completely eroded away, claimed by the sea due to the sea-level rise associated with global warming or assimilated by other islands. The North Thiladhunmathi Atoll administrative division is governed by an Atoll Council. The atoll council was created in 2011 with the enactment of the Decentralization Bill, which saw the introduction of local governance to the country. The secretariat of the atoll council is located on Dhidhdhoo. The atoll is