Yunnan is a province of the People's Republic of China, located in the far southwest of the country. It spans approximately 394,000 square kilometres (152,000 sq mi) and has a population of 45.7 million (2009). The capital of the province is Kunming, formerly also known as Yunnan. The province borders Vietnam, Laos and Burma.Yunnan is situated in a mountainous area, with high elevations in the northwest and low elevations in the southeast. Most of the population lives in the eastern part of the province. In the west, the altitude can vary from the mountain peaks to river valleys as much as 3,000 metres (9,800 ft).