I've stayed at Tria twice now - on the most recent trip for 10 days with my mum. The hotel is located at Yeoksam which is very convenient. Only a few minutes walk to the subway station (line 2) and less than 10 minutes to Gangnam station. Despite being in a busy area, the hotel rooms are very quiet, spacious for Seoul and spotlessly clean with good amenities (including toiletries). There are a bunch of good cafes and eateries around the hotel and a nice alternative to staying in bustling Gangnam. It's my go to place in Seoul now!