His fourth journey in 1883-1885 was to Sining (the great trade centre of the Chinese borderland), and thence through northern Tibet (crossing the Altyn Tagh to Lop Nor), and by the Cherchen-Keriya trade route to Khotan.
Both are directed and controlled by the high Chinese officials residing at Lhasa, Sining Fu; and the capital of the Chinese province of Szechuen.
Northeastern Tibet or Amdo, and also a portion of Khamdo, are under the supervision of a high official (Manchu) residing at Sining Fu in Kansuh, whose title is Imperial Controller-General of Koko Nor.
Minor roads go from Sining Fu in the Chinese province of Kansuh via Tsaidam and the Tang la pass to Nagchuka and Lhasa.
Then pushing on southwards, he crossed the Nienchen-tang-la and entered the Dam district near the Lhasa-Sining high road.