It is the one named Starbucks Famille Park. Once you get out from exit 4, you can see it just beside the JW Marriott Hotel. And it is not hard to find it too since the exterior is a geometric glass dome structure reflective of urban Seoul. When you enter the cafe, you can see the interior features like floors, walls, pillars, chairs, and tables are all made of wood. The most special thing in the cafe is there is a big atrium in the middle. At there, you can see the Starbucks envelopes around the center and the escalator going down to other parts of the mall. I personally think that is the most pretty spot if you wish to take photos there. The cafe itself is really big and fancy.