Laos is a landlocked country in Southeast Asia and the thickly forested landscape consists mostly of rugged mountains, the highest of which is Phou Bia at 9,242 feet (2,817 m), with some plains and plateaus. The Mekong River forms a large part of the western boundary with Thailand, whereas the mountains of the Annamite Chain form most of the eastern border with Vietnam.
The climate is tropical and monsoon. There is a distinct rainy season from May to November, followed by a dry season from December to April. Local tradition holds that there are three seasons (rainy, cold and hot) as the latter two months of the climatologically defined dry season are noticeably hotter than the earlier four months. The capital and largest city of Laos is Vientiane and other major cities include Luang Prabang, Savannakhet (city)Savannakhet and Pakxe.
