The bridges and tunnels across the Yangtze River carry rail and road traffic across China's longest and largest river and form a vital part of the country's transportation infrastructure. The river bisects China proper from west to east, and every major north–south bound highway and railway must cross the Yangtze. Large urban centers along the river such as Chongqing, Wuhan, and Nanjing also have urban mass transit rail lines crossing the Yangtze.
Pontoon bridges have been used by militaries for two thousand years on the Yangtze, but until the completion of the Wuhan Yangtze River Bridge in 1957, there were no permanent bridges along the main stretch of the river known as Chang Jiang (the "Long River"), from Yibin to the river mouth in Shanghai, a distance of 2,884 km (1,792 mi). Since then, over 75 bridges and six tunnels have been built over this stretch, the overwhelming majority since 1990. They reflect a broad array of bridge designs and, in many cases, represent significant achievements in modern bridge engineering. Several rank among the world's longest suspension, cable-stayed, arch bridges, truss and box girder bridges as well as some of the highest and tallest bridges.
Upriver from Yibin, bridge spans are more common along the Jinsha and Tongtian sections where the Yangtze is much narrower, although numerous new bridges are being added. The oldest bridge still in use is the Jinlong, a simple suspension bridge over the Jinsha section of the river in Lijiang, Yunnan that was originally built in 1880 and rebuilt in the 1936.[1]