The Republic of Equatorial Guinea (República de Guinea Ecuatorial, Spanish pronunciation: [re̞ˈpuβ̞lika ð̞e̞ ɣ̞iˈne̞a e̞kwato̞ˈɾjal]) is a country in Central Africa. It is one of the smallest countries in continental Africa, and comprises two regions: a Continental Region (Río Muni); and an Insular Region containing Annobón island, Bioko island (formerly Fernando Po) where the capital of Malabo is situated, and several offshore islands like Corisco. Annobón is the southernmost island of Equatorial Guinea and is situated just north of the equator. Bioko island is the northernmost point of Equatorial Guinea. Between the two islands and to the east is the mainland region. Equatorial Guinea is bordered by Cameroon on the north, Gabon on the south and east, and the Gulf of Guinea on the west, where the island nation of São Tomé and Príncipe is located between Bioko and Annobón. Formerly the colony of Spanish Guinea, its post-independence name is suggestive of its location near both the Equator and the Gulf of Guinea. It is one of the few territories in mainland Africa where Spanish is an official language, besides the Spanish exclaves of Ceuta and Melilla. Equatorial Guinea is the second smallest country in continental Africa in terms of population. (Seychelles, The Gambia, Rwanda, and São Tomé and Príncipe are smaller in terms of area, and the Sahrawi Arab Democratic Republic has a smaller population but is disputed.) It is also the smallest United Nations member from continental Africa. The discovery of sizeable petroleum reserves in recent years is altering the economic and political status of the country. Despite its name, no part of Equatorial Guinea's territory lies on the equator. The Republic of Equatorial Guinea is located in west central Africa. Bioko Island lies about 40 kilometers (25 mi.) from Cameroon. Annobón Island lies about 595 kilometers (370 mi.) southwest of Bioko Island. The larger continental region of Rio Muni lies between Cameroon and Gabon on the mainland. Near to the continental region the are located the islands of Corisco, Elobey Grande, Elobey Chico, and adjacent islets.