Perhaps no other area of comparable size presents such geographical, racial, climatic, political, linguistic and economic complexities as are found in Southeast Asia. This region may be delimited roughly as a parallelogram extending southeastward from the Burma-Assam-Sikang frontier through Burma, Thailand, and Indochina and including part of Yunnan and all of the Malay peninsula with the adjacent islands. Those who prefer their geography in circles may think of Southeast Asia as the mainland and peripheral islands embraced within a circle having Bangkok as a focus with a radius of 1000 miles; i.e. from Singapore to Fort Hertz and from Brunei to Chitta-gong.