Aerial photo taken on July 1, 2018 shows bullet trains running on a bridge in Nanning, capital of south China's Guangxi Zhuang Autonomous Region. China updated the country's train diagram on Sunday. (Xinhua/Huang Xiaobang)

Aerial photo taken on July 1, 2018 shows bullet trains running on a bridge in Nanning, capital of south China's Guangxi Zhuang Autonomous Region. China updated the country's train diagram on Sunday. (Xinhua/Huang Xiaobang)

Aerial photo taken on July 1, 2018 shows a bullet train station in Nanning, capital of south China's Guangxi Zhuang Autonomous Region. China updated the country's train diagram on Sunday. (Xinhua/Huang Xiaobang)