A good hotel close to Dongdaemun Gate is Hotel Pj Myeongdong (rated 8.5/10 from 939 reviews).
Lotte Hotel World is the most recommended hotel near Lotte World on HotelsCombined (scoring 8.4 over 1,022 reviews).
A good hotel near Yeouido Park is Kensington Hotel Yeouido Seoul, which has been rated 8.2/10 by 579 HotelsCombined user reviews.