It is situated on the middle to lower reaches of the Mekong, known as the Lancang in China, and the Salween, or the Nu. Bordering prefectures are Pu'er to the southeast, and Baoshan and Dali to the northwest. It also borders Burma's Shan State. Elevations within the prefecture range from 450 to 3,504 meters (1,480 to 11,496 ft). The Western Han Dynasty (206BC-24AD) placed Lincang in the Yizhou shire after conquering the ancient Ailao Kingdom. During the Tang (618-907) and Song (960-1279) dynasties, it belonged to the Nanzhao and Dali states respectively. Lincang lies at the bottom of the Hengduan Mountains and Nushan Mountain in western Yunnan. The terrain here slopes from southeast to southwest. There are many rivers which pass through or spring from Lincang. The Tropic of Cancer runs across the city and lends it a subtropical climate but which also combines with the cooler climate of the adjacent mountains.