Passengers ride Beijing Subway Line 10 on May 5, 2013. The last three stations were opened to complete the city's second loop subway line on Sunday. With 45 stations, the 57-kilometer line takes 104 minutes to make a complete loop. [Photo/Xinhua]

Passengers look at a train map and timetable at Jiaomen East Station at Beijing Subway Line 10 on May 5, 2013.[Photo/Xinhua]

Passengers ride on Beijing Subway Line 10 on May 5, 2013. [Photo/Xinhua]

Two passengers prepare to get on a train for Beijing Subway Line 10 on May 5, 2013.[Photo/Xinhua]