The longest bridge over water (aggregate length) is 48.3 km (30.01 mile), achieved by the Hong Kong-Zhuhai-Macau bridge, crossing over the Pearl River Delta in China, opened on 23 October 2018.Under construction for nearly 7 years, the estimated cost of the construction is approximately US $15.6 billion (¥ 110 billion). The entire length of the bridge is 55 km, including its 6.7 km undersea tunnel. The bridge was scheduled to open in 2016 but was delayed due to legal enquiry on the bridge's environmental impact. The bridge will have a 24 hour shuttle bus service to allow commutes to travel across the bridge.The bridge will significantly reduce the travel time between the three major cities of Zhuhai, Macau, and Hong Kong to less than one hour.