T'u-men

Article V.—In consideration of the numerous difficulties arising from the authority exercised by local officials over the legal traffic at such places on the boundary as I-chou, Hui-ning, and Ch’ing-yuan, it has now been decided that the people on the frontier shall be free to go to and fro and trade as they please at Ts’e-men and I-chou on the two sides of the Ya-lu River, and at Hun-ch’un and Hui-ning on the two sides of the T’u-men River.

Source: wiktionary

We may also expect to hear that a Corean Consulate is to be established at Vladivostok; the opening of the Tʻu-mên river will, no doubt, be secured and telegraphic communication established with Vladivostok and such other places as may be necessary.[…]The Tʻu-mên river flows close to the borders of Manchuria and its opening will probably increase the serviceableness of Possiet, which is near its mouth.

Source: wiktionary

Hui-ning and Hoi Ryöng (42° 22' N and 129° 43' E) was a city on the T'u-men River, which the Chinese in Ninguta used as their main market for trade with the Koreans (LPCL 3, 4b).

Source: wiktionary

In the 1380s the tribe moved southward and came to the lower valley of the T’u-men 圖們 River and finally settled down around Wo-mu-ho 斡木河, the present Hoeryong 會寧, in north Korea.

Source: wiktionary