The world's longest bridge is in China - the Hangzhou Bay Bridge which is 36 kms and spans the Hangzhou Bay. The bridge links Haiyan, Jiaxing City to Cixi, Ningbo City in Zhejiang Province. It will cut the length of the road trip from Shanghai to Ningbo, a busy port, by 120 km. And is designed to last 100 years. It is a cable-stayed structure built at a cost of 11.8 billion yuan (US$ 1.69 billion).
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Longest sea bridge in the world: A 22-mile bridge that its builders claim is the world's longest sea-crossing structure is south of the Shanghai.
The bridge links Shanghai to the industrial city of Ningbo across Hangzhou Bay, cutting the distance between them from about 250 miles to just 50 miles.