Staff members work at the construction site of the Liusanzhai tunnel of the middle line of the Chengdu-Chongqing high-speed railway in southwest China's Chongqing, Feb. 19, 2024. The middle line of the Chengdu-Chongqing high-speed railway will slash the travel time between the two cities to just 50 minutes after completion.(Photo: Xinhua)

An aerial drone photo shows staff members working at the construction site of the Xuantianhu bridge of the middle line of the Chengdu-Chongqing high-speed railway in southwest China's Chongqing, Feb. 19, 2024. The middle line of the Chengdu-Chongqing high-speed railway will slash the travel time between the two cities to just 50 minutes after completion.(Photo: Xinhua)

An aerial drone photo shows the construction site of the Xuantianhu bridge of the middle line of the Chengdu-Chongqing high-speed railway in southwest China's Chongqing, Feb. 19, 2024. The middle line of the Chengdu-Chongqing high-speed railway will slash the travel time between the two cities to just 50 minutes after completion.(Photo: Xinhua)

An aerial drone photo shows staff members working at the construction site of the Xuantianhu bridge of the middle line of the Chengdu-Chongqing high-speed railway in southwest China's Chongqing, Feb. 19, 2024. The middle line of the Chengdu-Chongqing high-speed railway will slash the travel time between the two cities to just 50 minutes after completion.(Photo: Xinhua)