Why is Xi 'an, Shaanxi a treasure trove of geomantic omen?

Because xi 'an has an emperor since ancient times, although he is not from Shaanxi, he is called the emperor in Xi 'an. Finally, Zhu Yuanzhang of the Ming Dynasty was afraid that another emperor in Shaanxi would rob him of his throne, so he built a bell tower and drum tower to suppress it. Now that the subway is open, the emperor appears again.