Didn't use the swimming pool but used the nice little gym. Friendly and polite staff, a lot of food places around, walkable distance to shopping places, next to a metro station - city hall.
Clean and tidy room, love the bidet, comfortable stay, strong heating, very warm, had to open some window.
Snowed when we stayed, pretty around, not blocked by high buildings.
Got a wowpass machine at the lobby, didn't have to get at airport or metro station.
Nice area to walk around Namdaemun market and underground market, close to department stores and MyeongDong.