The Shenzhen-Zhongshan Link in south China's Guangdong Province will be officially open to traffic at 3 p.m. on June 30. 

The 24-kilometer passage starts at the Shenzhen airport interchange and connects with Ma'anshan Island in Zhongshan across the Pearl River. Upon opening, the time it takes to travel between Zhongshan and Shenzhen will be cut from two hours to less than 30 minutes.

The megaproject consists of one underwater tunnel, two bridges and two artificial islands, making it one of the most difficult cross-sea cluster projects in the world, with 10 world records.

With a span of 1,666 meters, the Shenzhen-Zhongshan Bridge boasts the world's largest span for a fully offshore steel box girder suspension bridge. It has the world's highest air traffic clearance altitude at 76.5 meters. It also holds the world record with the largest offshore suspension bridge anchor of 1 million tonnes and the world's highest wind resistance test speed for a suspension bridge at 88 meters per second.

The west artificial island is a new landmark on Lingdingyang Bay.

The Shenzhen-Zhongshan tunnel is the world's longest and widest underwater steel-shell concrete tunnel. The engineering design plan of the Shenzhen-Zhongshan Link underwent many rounds of demonstration, and the plan combining bridge and tunnel was finally adopted.

Qian Qihu, an academician from the Chinese Academy of Engineering, said that it cannot work to build a tunnel under the rock layer and pass through 11 fault structures. The cutter head of the shield machine would be stuck by the broken rocks, which is very risky, so the "bridge-tunnel combination" solution was adopted.

The Shenzhen-Zhongshan Link is expected to handle more than 80,000 vehicles a day after it opens, according to an estimate released by the Shenzhen Municipal Bureau of Transportation.

Guangdong's three pilot free trade zones – Qianhai in Shenzhen, Nansha in Guangzhou and Hengqin in Zhuhai – will be connected through the link.