Pulau Merapas is the outer and E island off the E side of Pulau Bintan. It is 63m high, covered with trees, and steep-to 0.3 mile offshore.
Pulau Mapor (Pulau Mapur) lies with its S extremity about 10 miles N of Pulau Beruan. A prominent 107m high hill stands on the NW point of the island.
Pulau Sentut (Sentoet), 44m high and of sugarloaf form, lies about 2 miles NW of the NE end of Pulau Mapor. It is steep-to on the N side, but a reef extends about 0.5 mile from its S end.