The metro enters the station in Seoul, South Korea. I find this frame interesting, mainly because of the strict geometry between the train and the column standing on the left side of the image. There is also the round sign on the column, which contrasts with the straight horizontal and vertical lines. The more I look at the image, the more I enter in depth, and the more I discover that it contains new layers under the obvious visible ones.
It is like in everyday life: there is always more than what we perceive at first glance.