Which river forms most of the border between Laos and Thailand?
River systems of Thailand Mekong River Commission. The extreme seasonal variations in flow and the presence of rapids and waterfalls have made navigation extremely difficult. Approximately half the river's length is in China, where it is known as the "Lancang Jiang" (澜沧江 Láncāng Jiāng) or "Meigong" in Chinese (). The river forms the border between Myanmar and Laos for , at the end of which it meets the tributary Ruak River at the Golden Triangle. This point also marks the division between the "Upper" and "Lower Mekong". The river then divides Laos and Thailand, before a stretch passing through Laos alone. It is known
Malaysia–Thailand border Malaysia–Thailand border The Malaysia–Thailand border consists of both a land boundary across the Malay Peninsula and maritime boundaries in the Straits of Malacca and the Gulf of Thailand/South China Sea. Malaysia lies to the south of the border while Thailand lies to the north. The Golok River forms the easternmost 95 km stretch of the land border. The land border is based on the 1909 treaty between Thailand, then known as Siam, and the British which started to exert its influence over the northern Malay states of Kedah, Kelantan, Perlis, Perak and Terengganu in the early 20th century. The four