Four-fifths of Peninsular Malaysia is covered by rainforest and swamp. The northern regions are divided by a series of mountain ranges that rise abruptly from the wide, flat coastal plains. The highest peaks, Gunong Tahan (2,190 m/7,185 ft) and Gunong Korbu (2,183 m/7,162 ft), are in the north central region. The main watershed follows a mountain range about 80 km (50 mi) inland, roughly parallel to the west coast. The rivers flowing to the east, south, and west of this range are swift and have cut some deep gorges, but on reaching the coastal plains they become sluggish. The western coastal plain contains most of the country's population and the main seaports, George Town (on the offshore Pulau Pinang) and Kelang (formerly Port Swettenham). The eastern coastal plain is mostly jungle and lightly settled. It is subject to heavy storms from the South China Sea and lacks natural harbors.
Sarawak consists of an alluvial and swampy coastal plain, an area of rolling country interspersed with mountain ranges, and a mountainous interior. Rain forests cover the greater part of Sarawak. Many of the rivers are navigable. Sabah is split in two by the Crocker Mountains, which extend north and south some 48 km (30 mi) inland from the west coast, rising to over 4,100 m (13,450 ft) at Mt. Kinabalu, the highest point in Malaysia. Most of the interior is covered with tropical forest, while the western coastal area consists of alluvial flats making up the main rubber and rice land.