If you go to Pohang, there is a strange rolling bridge. You see it as a pushover, but the structure shakes a lot because of the steps people roll to the top at once. It's called Gongjin, or if people roll their feet at the same time in a health club on the high floor of a building, the building shakes. But you can experience this in an open place. I remember seeing my ancestors every step of the way. Of course, Pohang Steel installed it to show off its technology, so it's safe, but the dizziness can't be helped Let's go up when life is dry. Pohang-Spacewalk