Who left Yangguan in the west for no reason, which province does Yangguan refer to?

Yangguan refers to the present Gansu Province, which is located in the Gufengtan area in the southwest of Dunhuang City.

Origin of the name of Yangguan: In the Western Han Dynasty, Guansai was located in the northwest of China, which was named Yangguan because it was south of Yumenguan.

China emphasized geomantic omen in ancient times. On this basis, a variety of statements have been formed. After a long time, everyone agrees that the south of the mountain is sunny and the north of the water is cloudy. Because it is in the south of Yumenguan, it is called Yangguan. Yangguan and Yumenguan are both important passes for the Han Dynasty to the Western Regions.