This aerial photo taken on Nov 28, 2023 shows a high-speed passenger train running along the Sichuan-Qinghai railway. [Photo/Xinhua]

China has extended its transportation network by building high-speed railways and improving freeways this year, according to the Ministry of Transport on Thursday.

"This year, China built 1,700 kilometer of high-speed railways, built and renovated more than 7,000 km of freeways, added and improved 1,000 km of high-grade waterways, built two civil aviation airports, and added more than 360 km of urban railway networks," said Li Yang, vice-minister of transport, at a news conference in Beijing.

A total of 3,461 border villages have access to postal services, he said, adding that the construction of some major infrastructure projects has been accelerated, such as the Shenzhen-Zhongshan bridge, a 24-kilometer bridge-island-tunnel project in South China's Guangdong province; and the Pinglu Canal, a major project of China's new western land-sea corridor in the Guangxi Zhuang autonomous region.

"We have completed the undersea tunnel section this year and the bridge is expected to open to traffic in the first half of next year," Li said.

With a length of 6.8 km and a width of 46 meters, the two-way eight-lane tunnel is the largest and widest undersea steel shell concrete tube tunnel in the world.