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 .
The island is a heavily eroded volcano over three million years old . It is surrounded by other smaller islands including Ilheu Bom Bom , Ilhéu Caroço , Tinhosa Grande and Tinhosa Pequena .