In the absence of preciser indications, it is reasonable to suppose that the Plain of Tenduc, with its numerous towns and villages, was the extensive and well-cultivated plain which stretches from the Hwang-Ho, past the city of Kuku-Khotan, or “Blue Town.”  This tract abounds in the remains of cities attributed to the Mongol era.  And it is not improbable that the city of Tenduc was Kuku-Khotan itself, now called by the Chinese Kwei-hwa Ch’eng, but which was known to them in the Middle Ages as Tsing-chau, and to which we find the Kin Emperor of Northern China sending an envoy in 1210 to demand tribute from Chinghiz.  The city is still an important mart and a centre of Lamaitic Buddhism, being the residence of a Khutukhtu, or personage combining the characters of cardinal and voluntarily re-incarnate saint, as well as the site of five great convents and fifteen smaller ones.  Gerbillon notes that Kuku Khotan had been a place of great trade and population during the Mongol Dynasty.

[The following evidence shows, I think, that we must look for the city of Tenduc to Tou Ch’eng or Toto Ch’eng, called Togto or Tokto by the Mongols.  Mr. Rockhill (Diary, 18) passed through this place, and 5 li south of it, reached on the Yellow River, Ho-k’ou (in Chinese) or Dugus or Dugei (in Mongol).  Gerbillon speaks of Toto in his sixth voyage in Tartary. (Du Halde, IV. 345.) Mr. Rockhill adds that he cannot but think that Yule overlooked the existence of Togto when he identified Kwei-hwa Ch’eng with Tenduc.  Tou Ch’eng is two days’ march west of Kwei-hwa Ch’eng, “On the loess hill behind this place are the ruins of a large camp, Orch’eng, in all likelihood the site of the old town” (l.c. 18).  M. Bonin (J.  As. XV. 1900, 589) shares Mr. Rockhill’s opinion.  From Kwei-hwa Ch’eng, M. Bonin went by the valley of the Hei Shui River to the Hwang Ho; at the junction of the two rivers stands the village of Ho-k’au (Ho-k’ou) south of the small town To Ch’eng, surmounted by the ruins of the old square Mongol stronghold of Tokto, the walls of which are still in a good state of preservation.—­(La Geographie, I. 1901, p. 116.)

On the other hand, it is but fair to state that Palladius (21) says:  “The name of Tenduc obviously corresponds to T’ien-te Kiun, a military post, the position of which Chinese geographers identify correctly with that of the modern Kuku-hoton (Ta tsing y t’ung chi, ch. on the Tumots of Kuku-hoton).  The T’ien-te Kiun post existed under this name during the K’itan (Liao) and Kin Dynasties up to Khubilai’s time (1267); when under the name of Fung-chow it was left only a district town in the department of Ta-t’ung fu.  The Kin kept in T’ien-te Kiun a military chief, Chao-t’ao-shi, whose duty it was to keep an eye on the neighbouring tribes, and to use, if needed, military force against them.  The T’ien-te Kiun district was hardly greater in extent than the modern aimak of Tumot, into which Kuku-hoton was included since the 16th century, i.e. 370 li from north to south, and 400 li from east to west; during the Kin it had a settled population, numbering 22,600 families.”