Aerial photo taken on Oct. 27, 2019 shows a high-speed train running on the Guanting Lake Bridge section of Beijing-Zhangjiakou high-speed railway in Zhangjiakou, north China's Hebei Province. The construction of each station along the Beijing-Zhangjiakou high-speed railway is to be completed soon, following the operational test of each station. Photo:Xinhua

Photo taken on Nov. 15, 2019 shows a high-speed train running on the Beijing-Zhangjiakou high-speed railway in Zhangjiakou, north China's Hebei Province. The construction of each station along the Beijing-Zhangjiakou high-speed railway is to be completed soon, following the operational test of each station. Photo:Xinhua

Photo taken on Nov. 27, 2019 shows the Huailai Station along the Beijing-Zhangjiakou high-speed railway in Zhangjiakou, north China's Hebei Province. The construction of each station along the Beijing-Zhangjiakou high-speed railway is to be completed soon, following the operational test of each station. Photo:Xinhua

A high-speed train runs on the Beijing-Zhangjiakou high-speed railway in Zhangjiakou, north China's Hebei Province, Oct. 25, 2019. The construction of each station along the Beijing-Zhangjiakou high-speed railway is to be completed soon, following the operational test of each station. Photo:Xinhua

Aerial photo taken on Nov. 27, 2019 shows the Huailai Station along the Beijing-Zhangjiakou high-speed railway in Zhangjiakou, north China's Hebei Province. The construction of each station along the Beijing-Zhangjiakou high-speed railway is to be completed soon, following the operational test of each station. Photo:Xinhua

Photo taken on Nov. 28, 2019 shows the Xuanhuabei Station along the Beijing-Zhangjiakou high-speed railway in Zhangjiakou, north China's Hebei Province. The construction of each station along the Beijing-Zhangjiakou high-speed railway is to be completed soon, following the operational test of each station. Photo:Xinhua

A high-speed test train runs past the Huailai Station along the Beijing-Zhangjiakou high-speed railway in Zhangjiakou, north China's Hebei Province, Nov. 27, 2019. The construction of each station along the Beijing-Zhangjiakou high-speed railway is to be completed soon, following the operational test of each station. Photo:Xinhua

Aerial photo taken on Oct. 21, 2019 shows a high-speed train running on the Beijing-Zhangjiakou high-speed railway in Zhangjiakou, north China's Hebei Province. The construction of each station along the Beijing-Zhangjiakou high-speed railway is to be completed soon, following the operational test of each station. Photo:Xinhua