Helsinki, Finland, I have been there several times. I have a natural familiarity with this city as if I had lived in it all my life. Once our family traveled to several Nordic countries. We had time to visit the city. On the premise that I had been there once ten years ago, I took them to walk to a "banknote shop" on a small street. My companions and daughters were shocked by my "old horse knows the way" abilities. They didn't understand me. They asked me, "This is not Beijing, it's the capital of Finland, Helsinki. How do you know it so well?" The most surprising thing about Helsinki is the white night. We went in July, so there was hardly any dark sky here.