Thailand, formerly Siam, officially Kingdom of Thailand, constitutional monarchy in South East Asia, bordered by Myanmar (Burma) to the north and west, by Laos to the north-east, by Cambodia and the Gulf of Thailand (Siam) to the south-east, by Malaysia to the south, and by the Andaman Sea to the south-west. The total area of Thailand is 513,115 sq km (198,114 sq mi). The capital and largest city is Bangkok.