The territory consists of a mainland area and the islands of Bioko, Fernando Po, Pigalu, Elobey Grande, Elobey Chico and Corisco. Rio Muni or the mainland is a jungle enclave that rises sharply from the narrow coastal mangrove swamps towards the heavily forested African Plateau. The interior plain gives way to several valleys which are separated by low lying hills of the Crystal Mountains. The land is deeply cut by a number of rivers including the Mbini, Rio Campo and the Rio Muni. The islands are mainly of volcanic origin, mountainous and have rugged coastlines.
Equatorial Guinea has an equatorial climate which is hot and humid.
On Rio Muni the wet and dry season alternate, with the wet season from June to August and the dry season from December to February. Tornadoes and violent wind storms are also frequent. The principal ethnic group are the Fang or Fon who are divided into the Ntumu Fang north of the Nbini River and the Okak Fang to the south. Other ethnic minorities include the Kombe, Balengue, Bujebas, Bengas, Bubi, Fernandinos, Hausa, Ibo, Ibibo and Efik. The remainder follow local native tribal beliefs.