Peninsular

The mountains of South-East Asia grouped as peninsular fall into two types. The first type, as in Indo-China, is aligned along the coastal area of the peninsula. The second type forms the spine of the peninsula along the Tenasserim-Malaysia stretch. The first type includes the Truong San along the east coast and the Chuor Phnum Kravanh along the south-west coast of Indo-China. The former, `La Chaîne Annamitique' in French, extends southwards from Tonkin to the Mekong delta as a rugged highland. The chain is less of a continuous range than a series of plateaus. The high point, Ngoc Linh (2,598m), is in the central section. Both its northern and southern extremities exceed 2,400m in elevation. The highland rises precipitously from the east and descends gently towards the Mekong Valley. The composition is mainly of sandstones and limestones with some exposures of ancient crystalline rocks in the north. These highlands receive more than 2,000mm of rain annually and support tropical evergreen forests. In the extreme south, the basalt highlands have some large rubber estates.

Chuor Phnum Kravanh or simply Kravanh was formerly called the Cardamom Mountains. It extends about 160 km along the south coast of Cambodia with a south-east/north-west axis. Its eastern extension, Chuor Phnum Damrei, for merly called Elephant Mountains, is aligned north-south. The highest point, Phnum Aoral (2,929m), is located at the convergence of these two ranges in the north-east. Their western slopes receive nearly 5,000 mm of rain annually from the south-west monsoon. In contrast, the eastern slopes receive half of that. The indigenous people speak mainly Mon-Khmer. Commercial crops include cardamom and pepper.

The second type of peninsular range traverses south along the Myanmar-Thailand border all the way to Selangor in Malaysia. It commences with the Dawna Range east of Yangun with the high point, Mawkhi (2,080m), being on the Myanmar side. Further south, the range is called the Bilaktaung Range and it terminates short of the Kra Isthmus. Here also, the highest peak, Myinmoletkat (2,072m), lies west of the border. Despite its low elevation, the range acts as an effective climatic barrier. The western slopes receive nearly 3,000 mm of rain, while it is about 1,500m on the east side.

The Thai section of the Malay Peninsula has some elevated ranges exceeding 1,000m between the Kra Isthmus and Songkhla area. Southwards, the highlands of Malaysia commence at Bukut Bubus (1,145m) on the country's northern border. Peninsular Malaysia has several north-south trending ranges with granitoid topographic highs flanked by limestone, quartzite, and shale. Of these, the Banjaran Titiwangsa, including the Cameron Highlands, extends south to Selangor. Gunung Tahan (2,187m), the highest peak in Malaysia, lies on an eastern spur of the main range. The ranges are under dense tropical rain forests which are home to small groups of indigenous people (Orang Asli) of the Negrito type. These include the Jahai, Jakun, Semai, and Temiar.