Broadly speaking, consistent with Dong Fan's understanding, the west of Dunhuang, the north and south of Tianshan Mountain, Central Asia and West Asia are all "western regions";
Narrow sense: it is not the southern Xinjiang area under the jurisdiction of the Western Regions' Hufu in the Han Dynasty, but this part of Central Asia from the west of Congling to Persia (now Arabia Peninsula). The "narrow sense" of the "western regions" is mainly inseparable from the territorial changes in the Tang Dynasty. The administrative jurisdiction of the Han Dynasty was as far away as Balkhash Lake and Congling, and the prefectures and counties established in the Tang Dynasty were as far away as Persia.