During my stay in Korea I lived in Wangsimni area (surrounding a subway station carrying the same name), from where it took me just 10 minutes to get to my lab - on a lazy day. I stayed in a small Gosiwon very near the station (about 90 seconds away) with separate girls' and boys' floors. Right next to my place was one of the most famous Tteokbokki kiosks in the neighborhood.
Wangsimni station has a big E Mart, drugstore, Baskin'n'Robbins ice cream parlour and a small shopping arcade built to resemble Venice (pictures of the last I don't have).
There is some greenery around the station too, particularly on the side with the majority of exits (1 - 11 except for 6).
Daiso (exit 9 I believe) - it has only 2 floors but is a major life saver if you need whatever a student needs at a cheap price.
These soaps looked really interesting.
If you head towards Sangwangsimni and wander into the side streets to your left, you will find a nice neighborhood filled with small shops selling tons and tons of home made side dishes (and also a couple of cheaper supermarkets).
Hanyang University occupies a fairly steep hill close to the station and the campus is large and has many hidden surprises - statues, sculptures, staircases, dead ends...
This. Is. A. Bike. Though at first I wasn't so sure of that. Spotted near the riverside.
Finally we had our chimek night, watching people jog and work out on the riverside as we were stuffing ourselves with E Mart chicken. I tried to save it with Cass Light and it turned out to taste better than the regular version. =D This junk food was popularized by My Love From the Star - before it wasn't such a legend. I didn't know that, I thought they put it in the drama because it was popular with people - and yet it became only popular after the drama aired.