Príncipe is the smaller, northern major island of the country of São Tomé and Príncipe lying off the west coast of African in the Gulf of Guinea. It has an area of 136 square kilometres (53 sq mi) and a population of approximately 5,000. The island is a heavily eroded volcano speculated to be over three million years old, surrounded by smaller islands including Ilheu Bom Bom, Ilhéu Caroço, Tinhosa Grande and Tinhosa Pequena. Part of the Cameroon Line archipelago, Príncipe rises in the south to 948 metres at Pico de Príncipe, in a thickly forested area forming part of the Obo National Park.