The present city wall was mainly built in the Ming Dynasty (1368 - 1644), on the bases of the Tang Dynasty (618 - 907) City Wall. Before the Ming Dynasty was established, a hermit named Zhu Sheng told Zhu Yuanzhang (the first emperor of the Ming Dynasty) that if he wanted to found a strong country, he should 'build high city walls, store food as much as possible, and declare himself as the emperor later'. Zhu Yuanzhang adopted the advice and built the city wall after the Ming Dynasty was established.