China opened the Shenzhen-Zhongshan Link in Guangdong Province, south China, on Sunday, with trial operations scheduled to commence at 3 p.m.

The 24-kilometer passage starts at the Shenzhen airport interchange and connects with Ma'anshan Island in Zhongshan across the Pearl River. It cuts travel between Zhongshan and Shenzhen from two hours to approximately 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. It also holds 10 world records.

As a core transportation project in the Guangdong-Hong Kong-Macao Greater Bay Area, the new link spans about 24 kilometers and has been labeled the "transportation backbone" of the area, shouldering the vital task of seamlessly connecting the urban centers on either side of the Pearl River Estuary.

The link is a key component of the national expressway network G2518, located approximately 30 kilometers north of the Humen Bridge and 31 kilometers south of the Hong Kong-Zhuhai-Macao Bridge. It connects these vital transportation arteries.

The link, along with existing structures like the Hong Kong-Zhuhai-Macao Bridge, will form a network of cross-sea and cross-river passages in the Greater Bay Area, boosting connectivity of the city cluster, said Deng Xiaohua, head of Guangdong Provincial Communications Group.