Introduction to the ancient city of the Tang Dynasty: The ancient city of the Tang Dynasty was built on the top of a mountain and surrounded by a protective wall. The city administration rebuilt an exhibition hall for the Tang Dynasty King's March to the East. In the exhibition hall, there is a simulation exhibition room of the battlefield where Li Shimin, the king of Tang Dynasty, "camped out" in his palace, and the final decisive battle between Xue Li and Goguryeo general Ge Suwen in Anshi City (today's Haicheng City). Through a series of sound, light and electricity, the exhibition hall is built. The cooperation of modern science and technology reproduces the ancient battlefield scene of the Tang Dynasty's eastward expedition 1,300 years ago, giving people an immersive feeling.