APHUG Southeast Asia Physical MapOnline version APHUG map of Southeast Asia's physical features. by Grayson S. 1 Mekong River 2 Annam Mountains 3 Mekong Delta 4 Irrawaddy Delta 5 Irrawaddy River 6 Salween River 7 Indian Ocean 8 South China Sea 9 Gulf of Tonkin 10 Gulf of Thailand 11 Java River 12 Phillipine Sea 13 Pacific Ocean