I checked the subway line 2 in the map and it seems that the route is circular -- no ending station? From Chongwenmen, I plan to go to Qianmen which is only 1 station apart. Does subway line 2 has 2 trains from different directions? Or they only have 1 route and I won't have any difficulty which train to get? If they have 2, how will I know that I am getting the right direction?