Introduction to Zhonghe Cultural Plaza: The center of Zhonghe Cultural Plaza is the Tai Chi Diagram. There are three large circular rings on the periphery of the Tai Chi Diagram. The contents are the twelve hours, the twenty-four solar terms and the names of the hexagrams. Next to the circle is a square frame, which means the sky is round and the place is round. During the Yao period, Xihe was sent to observe the sky at Yunqiu Mountain, and twenty-two solar terms were determined here.