City Hall Station is a station on Seoul Subway lines 1 (Blue Line) and 2 (Green Line). As its name suggests, Seoul City Hall is located right next to the station. Deoksugung, a historic palace of the Joseon dynasty, is on the other side of the boulevard named Taepyeongno.
You must take the train to get from City Hall Station to Seoul City Hall
It's right next to each other, you can walk