The construction site of the Qinghuayuan Tunnel on the Beijing-Zhangjiakou intercity high-speed railway in the Haidian district of Beijing is seen on Tuesday. The 174-kilometer (108-mile) rail line is being built in preparation for the 2022 Winter Olympics, which will have events in Zhangjiakou, Hebei province, as well as in Beijing. Photo: VCG

High-speed trains on the Beijing-Zhangjiakou intercity high-speed railway will pass through the 6.02-kilometer Qinghuayuan Tunnel in five minutes. Photo: VCG

A tunneling shield is seen in the Qinghuayuan tunnel on the Beijing-Zhangjiakou intercity high-speed railway in Haidian district, Beijing, China, on Tuesday. The tunneling shield protects the construction site from the danger of a cave-in. Photo: VCG

The Beijing-Zhangjiakou intercity high-speed railway will have 10 stations when the project is completed. Photo: VCG

The Beijing-Zhangjiakou high speed railway is expected to begin operations at the end of 2019. It will reduce the commute time between Beijing and Zhangjiakou from three hours to one hour. Photo: VCGx