According to the currently recognized definition of the geographical location of the Qinghai-Tibet Plateau, the easternmost point of the plateau is Hengduan Mountain Range, so that the 3 18 National Road (the southern line of Sichuan and Tibet) officially enters the Qinghai-Tibet Plateau, which is Erlang Mountain (a part of Qionglai Mountain) in tianquan county, Ya 'an City, and after crossing Erlang Mountain, it enters the territory of Luding County, Ganzi Prefecture.
From the local ethnic and cultural point of view, the cultural characteristics of Luding County are still quite prominent, but when it comes to Kangding, it is an obvious mixed feature of Chinese and Tibetan. The Tibetan people generally recognize that the dividing line between Tibet and Tibet is Zheduo Mountain in the west of Kangding County. After Zheduo Mountain, xinduqiao and Tagong are the real Tibetan areas.
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