The two major landforms in Southeast Asia are the Malaysian Peninsula and the Malaysian Archipelago. The Malaysian Peninsula is composed of high mountain ranges ringed by deltas and coastal plains. The Malaysian Archipelago is located south of the peninsula, and it is one of the world's most active volcanic regions. Many of the islands in the archipelago are mountainous and formed by volcanoes.
Mountain ranges are one of the most prevalant geographic features in Southeast Asia. The Tenasserim mountain range is the central mountain range in the Malaysian Peninsula. Many other mountain ranges run parallel to the Tenasserim range. These ranges include the North Truong Son Range in Vietnam, the Bintang Mountains in Thailand and the Tahan Range in Malaysia and Thailand. Parts of the Himalayan foothills are located in Myanmar, which forms the northern part of the region.
The Malaysian Archipelago is also mountainous and contains many active volcanoes. This archipelago is composed of more than 25,000 islands. These islands are grouped in smaller archipelagos that include Indonesia, the Philippine Islands, and New Guinea and its surrounding islands. They are formed by four converging tectonic plates and shaped by active volcanoes. Famous volcanoes, such as Krakatoa, Merapi and Tambora, are all located in Indonesia.