Outside Tianyun Mountain.
In the territory of Xuzhou, there stood a strategic garrison city.
This garrison city was called Tianyun Pass, serving as the eastward passage from Xuzhou. Anyone entering or leaving Xuzhou without passing through here would have to skirt around Tianyun Mountain, adding several hundred miles to the journey. To a certain extent, Tianyun Pass was the vital throat of Xuzhou.
Chapter 147