This area is loosely dividable in two. The west is within the Northern Tibet Plateau and is entirely higher than 4000 meters: 'the Rooftop of the World'. The northern edge at first follows the Kunlun Mountains, then drops down through Qinghai(5) and down to the Tanggula(6) Mountains. The Kunlun average over 6000 meters and top out at 7,723 meters at Muztag(7) on Tibet's northern border. The plateau is studded with moderately large lakes; Siling(8) is the largest in this area.
To the east of the plateau the land consists of parallel ranges, separated by deep valleys. The Tanggula continue to mark the north for a while, but then the ranges turn southeast in several ranges collectively called the Hengduan. The Tanggula reach over 6000 meters at Xamardeqan and two peaks in southern Qamdo reach 6,600 meters. Between these heights flow the headwaters of the Irrawaddy(9) (the Nmai); the Salween (the Nu); the Mekong (the Lancang) and the Yangtze(10) (the Jinsha(11)) along the provincial border with Szechuan(12).
The overwhelming majority speak a Khams dialect(13), one of the Tibetan languages(14). Almost all are Lamist Buddhists.
All settlements, including the prefectures' administrative centers, are very small.
There are megalithic monuments as far east as the village of Amdo, north of the settlement of Nagqu. It is not known who built them(15).
Sino-Tibetans migrated across the area from further east. The group called by the Chinese as Ch'iang stayed in this area among other places. The ancestors of the Tibetans were probably in the same area initially, but were pushed south by the Ch'iang into what is now Yunnan. The Hsiung-Nu, a group from the north, later conquered the Ch'iang. Many of the Ch'iang migrated southwest during this overlordship. In the seventh century Tibetans re-entered the area from the south, bringing with them Mahayana Buddhism, which had now replaced the original Tibetan belief among the imperial elite.
subsequent religious developments
north
northeast
east
southeast
south of Qamdo
southwest of Qamdo and southeast of eastern Nagqu
south of western Nagqu, and west of Nagqu
(1) Formally Xizang or Hsi-Tsang Automonous Region in alternate transliterations from Chinese. Also spelled Si-tsang. It is called Bod or Bodyul in central Tibetan. The Chinese name could be translated as Western Treasurehouse.
(2) Zhongguo or Chung-hua in alternate transliterations from Chinese. The name could be translated as Middle Kingdom or Middle Land.
(3) Alternately transliterated from Chinese as Ch'ang-tu.
(4) Alternately transliterated from Chinese as Na-Ch'u.
(5) Alternately transliterated from Chinese as Tsing-hai. The name could be translated as Blue Sea.
(6) Also called the Tanglha.
(7) More than one mountain is called Muztag, in whole or part.
(8) Alternately transliterated from Chinese as Ch'i-lin.
(9) Or Ayeyararwady in standard Burmese.
(10) More properly the Chiang.
(11) Alternately transliterated from Chinese as Chin-sha.
(12) Transliterated from Chinese as Sichuan or Ssu-ch'uan. It can be translated as Four Rivers.
(13) Eastern, Southern, Western, Northern, Hbrugchu or Jone. These may be mutually unintelligible.
(14) Some people group Amdo, Kham, Central Tibetan and several other dialect groups together as one language, Tibetan, primarily for historical and political reasons; the speakers cannot understand each other, and the degree of tonality and the importance or existence of suffixes varies greatly.
(15) Some feel they are similar to Eurasian kurgans and attribute them to the group the Chinese called the Yueh-chih and who may have been the Tokharians, an Indo-European group. However, linguistic evidence for Tokharians is far to the northwest.