Jiuwandashan No.4 tunnel drilled through in S China's Guangxi

Workers celebrate at Jiuwandashan No.4 tunnel along the Guiyang-Nanning high-speed railway in Huanjiang Maonan Autonomous County, south China's Guangxi Zhuang Autonomous Region, Aug. 17, 2022.

The 15,485-meter Jiuwandashan No.4 tunnel was drilled through on Wednesday, marking the completion of all 108 tunnels of Guiyang-Nanning high-speed railway line.

The Guiyang-Nanning high-speed railway, with a maximum speed of 350 km per hour, is expected to go into service in 2023. (Xinhua/Cao Yiming)

Technicians work at Jiuwandashan No.4 tunnel along the Guiyang-Nanning high-speed railway in Huanjiang Maonan Autonomous County, south China's Guangxi Zhuang Autonomous Region, Aug. 16, 2022.

The 15,485-meter Jiuwandashan No.4 tunnel was drilled through on Wednesday, marking the completion of all 108 tunnels of Guiyang-Nanning high-speed railway line.

The Guiyang-Nanning high-speed railway, with a maximum speed of 350 km per hour, is expected to go into service in 2023. (Xinhua/Cao Yiming)

A worker operates at Jiuwandashan No.4 tunnel along the Guiyang-Nanning high-speed railway in Huanjiang Maonan Autonomous County, south China's Guangxi Zhuang Autonomous Region, Aug. 16, 2022.

The 15,485-meter Jiuwandashan No.4 tunnel was drilled through on Wednesday, marking the completion of all 108 tunnels of Guiyang-Nanning high-speed railway line.

The Guiyang-Nanning high-speed railway, with a maximum speed of 350 km per hour, is expected to go into service in 2023. (Xinhua/Cao Yiming)

Workers operate at Jiuwandashan No.4 tunnel along the Guiyang-Nanning high-speed railway in Huanjiang Maonan Autonomous County, south China's Guangxi Zhuang Autonomous Region, Aug. 16, 2022.

The 15,485-meter Jiuwandashan No.4 tunnel was drilled through on Wednesday, marking the completion of all 108 tunnels of Guiyang-Nanning high-speed railway line.

The Guiyang-Nanning high-speed railway, with a maximum speed of 350 km per hour, is expected to go into service in 2023. (Xinhua/Cao Yiming)

Workers are seen at Jiuwandashan No.4 tunnel along the Guiyang-Nanning high-speed railway in Huanjiang Maonan Autonomous County, south China's Guangxi Zhuang Autonomous Region, Aug. 16, 2022.

The 15,485-meter Jiuwandashan No.4 tunnel was drilled through on Wednesday, marking the completion of all 108 tunnels of Guiyang-Nanning high-speed railway line.

The Guiyang-Nanning high-speed railway, with a maximum speed of 350 km per hour, is expected to go into service in 2023. (Xinhua/Cao Yiming)

A technician works at Jiuwandashan No.4 tunnel along the Guiyang-Nanning high-speed railway in Huanjiang Maonan Autonomous County, south China's Guangxi Zhuang Autonomous Region, Aug. 16, 2022.

The 15,485-meter Jiuwandashan No.4 tunnel was drilled through on Wednesday, marking the completion of all 108 tunnels of Guiyang-Nanning high-speed railway line.

The Guiyang-Nanning high-speed railway, with a maximum speed of 350 km per hour, is expected to go into service in 2023. (Xinhua/Cao Yiming)

Workers operate at Jiuwandashan No.4 tunnel along the Guiyang-Nanning high-speed railway in Huanjiang Maonan Autonomous County, south China's Guangxi Zhuang Autonomous Region, Aug. 17, 2022.

The 15,485-meter Jiuwandashan No.4 tunnel was drilled through on Wednesday, marking the completion of all 108 tunnels of Guiyang-Nanning high-speed railway line.

The Guiyang-Nanning high-speed railway, with a maximum speed of 350 km per hour, is expected to go into service in 2023. (Xinhua/Cao Yiming)

Aerial photo taken on Aug. 16, 2022 shows the construction site of Jiuwandashan No.4 tunnel along the Guiyang-Nanning high-speed railway in Huanjiang Maonan Autonomous County, south China's Guangxi Zhuang Autonomous Region.

The 15,485-meter Jiuwandashan No.4 tunnel was drilled through on Wednesday, marking the completion of all 108 tunnels of Guiyang-Nanning high-speed railway line.

The Guiyang-Nanning high-speed railway, with a maximum speed of 350 km per hour, is expected to go into service in 2023. (Xinhua/Cao Yiming)

Aerial photo taken on Aug. 16, 2022 shows the construction site of the Guiyang-Nanning high-speed railway in Huanjiang Maonan Autonomous County, south China's Guangxi Zhuang Autonomous Region.

The 15,485-meter Jiuwandashan No.4 tunnel was drilled through on Wednesday, marking the completion of all 108 tunnels of Guiyang-Nanning high-speed railway line.

The Guiyang-Nanning high-speed railway, with a maximum speed of 350 km per hour, is expected to go into service in 2023. (Xinhua/Cao Yiming)