HONG KONG—The world’s longest sea bridge is set to open on Tuesday, snaking 34 miles across China’s Pearl River estuary to form a pillar of Beijing’s plan to merge 11 cities in its southern region into one megalopolis.
At 20 times the length of California’s Golden Gate Bridge, the six-lane crossing will link a regional economic zone of 70 million people, with a combined annual GDP of $1.51 trillion—almost twice that of the San Francisco Bay Area, and larger than the national economies of Australia, Spain or Mexico. The nine-year construction project joins a recently launched high-speed train to cut travel times and boost business ties between mainland Chinese manufacturing cities and the financial hub of Hong Kong as well as the gambling enclave of Macau.