The Ningbo section of the Jintang submarine tunnel, the world's longest subsea high-speed railway tunnel, starts construction on May 11. [Photo/WeChat account: nbfb0574]

The section of the Jintang submarine tunnel located in Ningbo, East China's Zhejiang province, started construction on May 11. The tunnel is the world's longest subsea high-speed railway tunnel.

The 16.18-kilometer tunnel, 2.4 times longer than the tunnel along the Hong Kong-Zhuhai-Macao Bridge, is an integral part of the Ningbo-Zhoushan railway, which connects Ningbo with the nearby island city of Zhoushan.

The Ningbo-Zhoushan railway starts at East Ningbo Station in Ningbo, passes by the city's Yinzhou district and Beilun district, Jintang Island, Cezi Island, and Fuchi Island, and ends in Baiquan town in Zhoushan.

The 26.99-billion-yuan ($3.88 billion) railway spans a distance of about 77 km, including 6.3 km of existing railway, and has seven stations, with trains operating at a maximum speed of 250 km per hour.

After its operation, it will take just 30 minutes to travel between Ningbo and Zhoushan and roughly one hour between Hangzhou and Zhoushan.