hi. i recommend myeongdong area. this is because it's good for shopping souvenirs,cosmetics n clothings. (not in myeongdong itself) staying at city hall station area is quite convenient. firstly, it's the green line and dark blue line. which means straight train to sinchon,ewha,hongik(aka hongdae) and dark blue means straight to seoul staiton. it's walkable to namdaemun market(which is then walkable to seoul station) also walkable to myeongdong. well don't do this in winter of course. i think myeongdong too many tourists, stuff not so cheap. i would recommend area nearby ewha university and sinchon area. for cosmetics, i recommend sinchon exit 3. y? very convenient. walk straight down u will pass by faceshop,tony moly,natural republic, etude,skinfood,innisfree,olivia,too cool for school at one road across and more. didn't walk whole area. oh ya and check out cn.konest.com it's in chinese. there's ecoupons to print for discounts shopping and food. quite good if you're a korean skincare and cosmetics user.