Atoll Baa or Maalhosmadulu South is an atoll in the Maldives. Located in the west of the atoll series of the Maldives, it consists of 75 islands in which 13 are inhabited with a population greater than 11,000 people spread over an area of 1,200 km2. It is located between latitudes 5 °23 'N and 4 °49' N. The remaining 57 islands are uninhabited, plus six islands that are being designed for tourism purposes. The atoll administration consists of two naturally separated atolls, called South Maalhosmadulu Atoll and Goidhoo Atoll. South Maalhosmadulu Atoll is 42 km long and 32 km wide and has 10 inhabited islands.
The Baa Atoll is also considered as an example of a rich biodiversity found in the Maldives, including extensive mangroves and a unique diversity, such as a benthic fauna among which rare corals include hydrozoans, bryozoans and sea slugs. In addition, the ringed form of the reefs is known as faroes, in Baa Atoll it has a reef with a unique structure in the Maldives. In addition, Baa Atoll hosts very significant concentrations of whale sharks and stingrays. The uninhabited island located at the southern end called Olhugiri on Baa Atoll is 13 km from Goidhoo Atoll. Olhugiri is well known for its unique natural vegetation and for having two of the only accommodation places of the Great Frigatebird in the Maldives. Also, other types of species such as sea turtles and Hawksbill turtles can be found. The Ministry of Fisheries of the Maldives has banned the capture of turtles or take eggs from Olhugiri, which extends to 11 other islands.