Tunnel under construction on Guiyang-Nanning high-speed railway in Guangxi

Aerial photo taken on March 30, 2022 shows a tunnel under construction on the Guiyang-Nanning high-speed railway in Hechi City, south China's Guangxi Zhuang Autonomous Region.

With a length of 482 km, the railway line will cut travel time from Nanning to Guiyang from over 10 hours to 2 and a half hours. (Xinhua/Zhang Ailin)

Workers work at a tunnel under construction on the Guiyang-Nanning high-speed railway in Hechi City, south China's Guangxi Zhuang Autonomous Region, March 30, 2022.

With a length of 482 km, the railway line will cut travel time from Nanning to Guiyang from over 10 hours to 2 and a half hours. (Xinhua/Zhang Ailin)

Workers work at a tunnel under construction on the Guiyang-Nanning high-speed railway in Hechi City, south China's Guangxi Zhuang Autonomous Region, March 31, 2022.

With a length of 482 km, the railway line will cut travel time from Nanning to Guiyang from over 10 hours to 2 and a half hours. (Xinhua/Zhang Ailin)

Workers work at a tunnel under construction on the Guiyang-Nanning high-speed railway in Hechi City, south China's Guangxi Zhuang Autonomous Region, March 30, 2022.

With a length of 482 km, the railway line will cut travel time from Nanning to Guiyang from over 10 hours to 2 and a half hours. (Xinhua/Zhang Ailin)

Workers work at a tunnel under construction on the Guiyang-Nanning high-speed railway in Hechi City, south China's Guangxi Zhuang Autonomous Region, March 30, 2022.

With a length of 482 km, the railway line will cut travel time from Nanning to Guiyang from over 10 hours to 2 and a half hours. (Xinhua/Zhang Ailin)