Compléter 1025bridgeVersion en ligne 1025 longest bridge par John E 1 longest cross Tourists kilometers drivers islands links cost between ceremony million president expert The world's sea bridge has opened . It Hong Kong and mainland China . It is 55 long and took 10 years to build . Special in the river support the bridge . There is also a 6 . 7 - kilometre tunnel for ships to sail over . The travel time mainland China and Macau will be cut by two - and - a - half hours . China's was at the opening . The bridge will link 68 people . Up to 29 , 000 cars will the bridge every day . A trade said the bridge will help China . can drive across the bridge , but local car owners need a permit . Most will take a shuttle bus . This will $8 - $10 .