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
Alif Dhaal Atoll Alif Dhaal Atoll Alifu Dhaalu Atoll (also known as Southern Ari Atoll or Ari Atholhu Dhekunuburi) is an administrative division of the Maldives. The separation of Ari Atoll (formerly Alifu Atoll) on March 1, 1984, into a Northern and a Southern section formed the two most recent administrative divisions of the Maldives, namely Alifu Alifu Atoll and Alifu Dhaalu Atoll. Alifu Dhaalu Atoll lies south of the line between the channels of Himendhoo Dhekunukandu and Genburugau Kandu. There is a beautiful ancient mosque in Fenfushi island having wooden decorated ceilings and lacquerwork panels. Buddhist remains, including a stupa, have been