ZHUHAI, China -- A bridge connecting this city in the southern Chinese province of Guangdong with Hong Kong and Macau will be completed by year-end and fully open to vehicular traffic in 2018, authorities told foreign media Wednesday.

The Hong Kong-Zhuhai-Macau Bridge, which will reportedly be among the world's longest at 55km, will let travelers drive from Hong Kong to Macau or Zhuhai in just half an hour. Work began in late 2009 toward a planned opening in late 2016 but ran into delays. Costs are expected to total 110 billion yuan ($15.9 billion).

The three cities are geographically close but separated by water. With Hong Kong under British jurisdiction and Macau controlled by Portugal until the late 1990s, economic exchanges among the three were minimal. The bridge is intended to help change that.

Other steps have been taken to make the area more investor-friendly, such as the designation of Zhuhai's Hengqin area as a free trade zone in 2015. The hope is to leverage the completion of the bridge into an opportunity to create an economic zone linking the three areas.