Mapao Spring is located in the northwest corner of Wangshubu Village, Dingzhuang Town, Guangrao County. The terrain here is low and flat, with dense rivers and ditches. A Beiling passes from the ground from east to west, forming a unique scenic spot in the north of Guangrao that integrates humanities and nature. According to legend, in 645 AD, Emperor Taizong of Tang, Li Shimin, personally led the three armies from Chang'an, Xijing, to the east and arrived here after going through untold hardships. It was midsummer at that time, and the soldiers were exhausted and hungry. They hurriedly dug wells to get water and cook. They dug dozens of wells in different locations, but the water they took out was bitter and difficult to drink. Li Shimin was extremely anxious. At this time, his mount neighed long, stood up on its hind legs, and kept digging the ground with its front hooves. Just where the horse's hooves stepped, a clear spring gushed out. The spring water was sweet and the soldiers were inexhaustible, which greatly boosted their morale. This spring saved Emperor Taizong of Tang from his emergency, so he named it "Mapao Spring". Mapao Spring gushes continuously, and the water is refreshing and sweet, while the water around it is very bitter, so people regard this spring as a sacred spring. Generation after generation of people have carefully protected it, and it has gone through more than a thousand years of ups and downs. When the Dayu Zhang project was built, it was necessary to dig a ditch (Wujia Dagou) here to build a bridge. In order to prevent the gushing spring water from affecting the construction, the construction team blocked the spring eye with cement. Since then, the ancient spring has stagnated, and its pleasant demeanor can no longer be seen.