Introduction to Double Rainbow Falling Colors: When Meihu Lake in the northeast of Dongqian Lake was not destroyed, in the 28th year of Daoguang reign of the Qing Dynasty (1848), the silt from the dredged lake was used to build a long embankment between Shaojiashan and Yangjiashan. Wulitang is seven or eight meters wide. There is a stone arch bridge at the beginning and end of the pond. It is called Lower Hong Bridge in the east and Shang Hong Bridge in the west. In late spring and early summer, after a thunderstorm, there is a rainbow hanging above and a bow bridge below. Therefore, the scene is named Double Rainbow Falling Color based on Li Bai's poem "Two waters hold a mirror, a double rainbow falls on the bridge."