Physical features of Southeast Asia include mountain ranges, plains, peninsulas, straights and islands. Vietnam and Indonesia are well-known for their mountain ranges. The tallest mountain in Southeast Asia is Hkakabo Razi in Myanmar, which is more than 19,000 feet high. Other notable features include the Tonle Sap Basin and the Mekong Lowlands in Cambodia. The islands and volcanoes of the Malaysian Archipelago are also part of Southeast Asia.
The Malay Peninsula is part of Southeast Asia and includes the countries of Thailand, Singapore and parts of Malaysia and Myanmar. This peninsula is divided by a central mountain range that includes Mount Tahan. Rivers flow to the East and West of the Peninsula. Pahang River is notable because it is the longest river in the Malay Peninsula, covering a total of 271 miles.
Many countries in Southeast Asia border the ocean, so the region has several straights, gulfs and deltas. These include the Straight of Malacca, the Singapore Straight and the Gulf of Thailand. Southeast Asia also includes over 25,000 islands located in the Malaysian Archipelago. The archipelago consists of several smaller island chains. These smaller archipelagos include Indonesia, the Philippine Islands, the Maluku Islands, and New Guinea and its surrounding islands.