The Baodai Bridge, also known as the Changqiao Bridge (literally, a longbridge), lies on the Daidai River running between Tantai Lake and the Suzhou section of the Grand Canal. It is one of the top ten famous bridges in ancient China and is one of the oldest bridges in China that is still extant. The BaodaiBridge was praised as “the unequalled bridge in the land of Wu” by the Qianlong Emperor. It was built during the reign of the Emperor Xianzong in the Tang dynasty. It is said that the bridge was named after the story that Wang Zhongshu, a provincial governor of the Tang dynasty, sold his jewel-decorated belt baodai 宝带 to finance the construction of the bridge. Yet another story goes that the bridge got its name because it looks like a jeweled belt floating on the water. Among old stone bridges along the Grand Canal, Baodai Bridge bears the longest length, the largest number of arches and the lightest weight. Baodai Bridge functions as a dike to connect between areas separated by water. The design of the bridge’s 53 arches not only is conducive to the flood relief of Taihu Lake, but also ensures the stability of the canals. The construction of the Baodai Bridge embodies the wisdom of the bridge builders in ancient China. These builders’ structural-mechanics-based use of “flexible piers” and “rigid piers” has made the Baodai Bridge an outstanding example in the history of bridge construction.