There are many ways to interpret definition of “Tibetan area”. If the “radiation area of Tibetan culture” is taken as base point, then the entire Tibetan area can be said to be vast.
Because, in addition to Tibetan Areas in China, such as: Tibet Autonomous Region, Yunnan Tibetan Region, Sichuan Tibetan Region, Gansu Tibetan Region, and Qinghai Tibetan Region, there are also Ladakh and Southern Tibet
Furthermore than above listed Tibetan regions, Bhutan, Nepal, Sikkim, and a part of Pakistan-controlled Kashmir (Jammu-Baltistan), as a region deeply radiated by Tibetan culture, should theoretically be considered as a part of Tibetan cultural region.
However, “Tibetan area” described in this article refers to the area within territory of the People’s Republic of China, that is, Tibetan living area in Tibet Autonomous Region, Yunnan Province, Sichuan Province, Qinghai Province, Gansu Province.
According to provincial administrative regions of modern China, there are Tibetan areas separately in Yunnan Province, in Sichuan Province, in Gansu Province, in Qinghai Province, and Tibet Autonomous Region on Tibet plateau.
If to follow traditional Tibetan culture, then there are three major Tibetan areas on Tibet plateau that are “U-tsang”, “Khampa”, and “Amdo”.
–Tibetan Regions, prefectures, counties —
Qinghai province (6 prefectures)
Sichuan province (2 prefectures & 1 Autonomous County)