 This line includes other volcanic islands in the Gulf of Guinea such as Annobón, Príncipe and São Tomé, along with the massive stratovolcano of Mount Cameroon.Unlike the three other islands which are extinct volcanoes, its last eruption occurred in 1923.Part of the Cameroon line, the flora and fauna of Pico Basilé and Bioko as a whole are similar to that of the montane regions of adjacent Cameroon and Nigeria.