Six-year-old Ma Mingze takes the train on Yanfang subway line in Beijing, capital of China, Dec. 30, 2017. Yanfang line started trial operation on Saturday. Located in Beijing's southwest suburbs, the Yanfang Line is China's first fully domestically developed automated subway. It has nine stations on its 14.4-km main line, linking the areas of Yanshan and Fangshan. The line is expected to carry 70,000 passengers daily. (Xinhua/Luo Xiaoguang)