Mainland Southeast Asia

Indochina Indochinese Peninsula Mainland Southeast Asia
Peninsulas of Asia
Countries	Myanmar, Cambodia, Laos, Malaysia, Thailand, Vietnam
Topographical map of mainland Southeast Asia

Mainland Southeast Asia, also known as the Indochinese Peninsula and previously Indochina, is the continental portion of Southeast Asia lying east of India and south of China, bounded by the Indian Ocean to the west and the Pacific Ocean to the east.

The Indochinese Peninsula projects southward from the Asian continent proper. It contains several mountain ranges extending from the Tibetan Plateau in the north, interspersed with lowlands largely drained by three major river systems running in a north–south direction: the Irrawaddy (serving Myanmar), the Chao Phraya (in Thailand), and the Mekong (flowing through Northeastern Thailand, Laos, Cambodia and Vietnam). To the south it forms the Malay Peninsula, on which are located Southern Thailand and Peninsular Malaysia; the latter is variably considered part of Mainland Southeast Asia or separately as part of Maritime Southeast Asia.

Mainland Southeast Asia contrasts with Maritime Southeast Asia, mainly through the division of largely land-based lifestyles in Indochina and the sea-based lifestyles of the Malay and Philippine archipelagos, as well as the dividing line between the Austroasiatic and Sino-Tibetan languages (spoken in Mainland Southeast Asia) and Austronesian languages (spoken in Maritime Southeast Asia).