China opens world's longest sea bridge

China has opened the world's longest sea bridge, a 55 km structure linking Hong Kong, Zhuhai, and Macau. Supported by three cable-stayed bridges and 400,000 tons of steel, it can withstand winds up to 340 km/h. The bridge includes a 6.7 km submerged tunnel and connects 11 cities in the Greater Bay Area. Completed in nearly nine years, it cost around $20 billion.

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