Sa Pa District is located in Lao Cai Province, north-west Vietnam, and 350 km north-west of Hanoi, close to the border with China. The Hoang Lien Son range of mountains dominates the district, which is at the eastern extremity of the Himalayas. This range includes Vietnam's highest mountain, Fan si pan, at a height of 3142m above sea level. The town of Sa Pa lies at an altitude of about 1600 m. The climate is moderate and rainy in summer (May—August), and foggy and cold with occasional snowfalls in winter.