Aerial photo taken on May 17, 2016 shows the bullet trains in Nanning, south China's Guangxi Zhuang Autonomous Region. The total mileage of railway lines in Guangxi Zhuang Autonomous Region has reached 5,191 km from 1,346.3 km in 1958. The railway has become a transportation artery and brought economic opportunities to Guangxi. (Xinhua/Huang Xiaobang)?