I will post a serie of articles on what to do / what to see in Seoul and in Korea. For the 1st article I will write about something that I consider worth to see in Seoul, but still quite unknown : The banpo Bridge (반포대교).
Indeed usually tourists don't know much about it, and don't go to see it. Even many of my Korean friends haven't seen it yet! You would miss something if you leave Korea before getting there.

