Sao Tom? and Princip?. A beach on the Ilheu das Rolhos island resort in the south of Sao Tom?and Princip? shaded by coconut trees and castanheiro trees (nut trees). Ilheu das Rolos is a tiny island, which until 1975 was private. It sits on the equator - for which a monument has been built to mark the exact point. Sao Tom?and Princip? is Africa's second smallest country with a population of 193 000. It consists of two mountainous islands in the Gulf of New Guinea, straddling the equator, west of Gabon.