This is a fun activity, but not for those with a height aversion. Located in Lotte World tower, this is an observation area where you get 360 degree views of Seoul. We visited at night, and it was gorgeous, but I'm biased because night views are my favorite. You can shop inside the tower before or after this activity, and there is a cafe on the observation deck level as well where you can purchase snacks or ice cream. I think this is a good activity if you like this sort of thing.