Tertre is a gallery cafe in Seoul that serves coffee and tea, located near the Naksan Fortress Wall in Changsin-dong. Drinking while looking out at Namsan and the Seoul City Wall through the full-length windows is the main draw. You must order on the first floor before going up to the second and third floors and the rooftop. It sits high on a slope, so it is hard to reach without a car, and the seating is uncomfortable.