FUZHOU, Sept. 28 -- China's fastest cross-sea high-speed rail started operation on Thursday, with trains running at a maximum speed of 350 km/h along the west coast of the Taiwan Strait.

A Fuxing bullet train G9801 departed from Fuzhou, the capital of southeast China's Fujian Province, at 9:15 a.m., marking the opening of the 277-km Fuzhou-Xiamen-Zhangzhou high-speed railway.

This is China's first cross-sea high-speed railway with a designed speed reaching 350 km/h, according to the China State Railway Group Co., Ltd., the country's railway operator. It has stops in the cities of Fuzhou, Putian, Quanzhou, Xiamen and Zhangzhou.

With a total investment of 53 billion yuan (about 7.4 billion U.S. dollars), the railway is the latest mega infrastructure project launched to boost connectivity in Fujian, whose transport options and efficiency have long been constrained by its mountainous terrain.

The new rail slashes travel time between Fuzhou and Xiamen, an economic hub and tourist hotspot in the province, to just under an hour. The fastest train trip used to take around 1 hour and 20 minutes.

The railway features a breathtaking sea view with 19.9 km of tracks built over the sea. It traverses three coastal bays -- Quanzhou Bay, Meizhou Bay and Anhai Bay -- via cross-sea bridges.

The railway has 84 bridges and 29 tunnels, which account for 85 percent of the total length, said Rao Huiming, vice general manager of Southeast Coast Railway Fujian Co., Ltd., the construction company of the railway route.

"This railway line brings together almost all challenges encountered during the construction of previous high-speed rail projects," said Li Pingzhuo, project manager of China Railway Siyuan Survey and Design Group Co., Ltd., the company that designed the railway project.

The construction of the three cross-sea bridges has successfully conquered challenges posed by strong winds, high waves, deep waters and the corrosive nature of the marine environment, Li said, adding that the railway has been fortified against earthquakes as it passes through an area with a high seismic risk.

As a key link in the railway, the 14.7-km Meizhou Bay cross-sea bridge is believed to be the country's first extradosed cable-stayed bridge on a sea-crossing high-speed railway.

The Quanzhou Bay cross-sea bridge is beefed up with windproof structures and technologies to allow trains to pass at the maximum speed even in 8-grade gales. The Anhai Bay Grand Bridge has the country's first ballastless track laid on a cross-sea bridge, a design that prevents the assails of flying rocks in windy weathers.

The railway also features various intelligent technologies, including the Internet of Things, edge computing and geographic information system, to ensure safe and sound operation, according to the China State Railway Group Co., Ltd.

Reporters onboard the G9801 said all seats are equipped with charging ports, while seats in business class cabins have intelligent touch-screen control panels.

Che Yanxue, the train conductor, said the Fuxing trains running on the line have more spacious seating areas, more comfortable inverter air conditioners and reduced noise levels. "The train runs very steadily. There is hardly any bump when the train crosses the sea."

This railway is the latest major addition to China's sprawling high-speed rail network. By 2022, China had 42,000 km of operational high-speed railway, ranking first in the world, and the length of high-speed rail regularly operating at 350 km per hour neared 3,200 km as of June 2022.

A circular issued by the Communist Party of China Central Committee and the State Council earlier this month designated Fujian as a demonstration zone for cross-Strait integrated development, with an aim of facilitating better connectivity and integration between Fujian and Taiwan.

This railway, the first in the province with a maximum speed of 350 km/h, will connect multiple city clusters and transform the areas of Fuzhou and Xiamen into a 1-hour living circle, officials said.

Cong Liang, deputy head of the National Development and Reform Commission, said an integrated multidimensional transportation network has been built in Fujian, making it technically possible to construct a high-speed transport passage linking the province with Taiwan.