JW Marriott Hotel Seoul
Street#126, House#56 Anam-dong 4(sa)-ga , Seongbuk-gu , Seoul
My first time traveling to Korea, and this is a top-notch hotel in every way. Rooms are great, service is excellent and one of the best gyms I've ever experienced at a hotel - just try not to laugh at all of the gym members being dressed in the exact same clothes (they actually give you gym clothes to wear if you want, including socks!) Very convenient to find food/amenities outside of the hotel since it is connected to one of the largest department stores and on the 10th floor of the department store are several good restaurants.