I was there in winter and it was fine. It's's good place to walk around and there are deer

(Open all year round) * Some facilities are closed on Mondays. Activity Information Feeding deer, natural experience site, butterfly experience hall * Registration is available on the official website. Operating Hours Ecological Forest 07:00-20:00 / June-August 07:00-21:00 Insect Garden 10:00-17:30 (Last admission: 17:00, Closed on Mondays) Butterfly Garden 10:00-17:30 (Last admission: 17:00, Closed on Mondays & Winter Season (November-April)) Eco Learning Center 10:00-18:00 (Admission is available only during event & exhibition period) Visitor Center Summer season: 10:00-18:00 / Winter season: 10:00-17:00 (Lunch time 12:00-13:00) * Nursing room, wheel chair and stroller rental available courtesy of #visitkorea website

Line 2: Ttukseom Station, Exit 8 or Line Bundang: Seoul Forest Exit 3

When you exit the station, there few shops or restaurants before you can reach the entrance of Seoul Forest.

You're going to take exit 3 at Seoul forest station. Once you're at street level, walk straight until you reach the 1st intersection and turn right, do not cross the street. When you turn right, you should see a car tunnel ahead. If you see the tunnel, continue walking down til you reach the next cross walk. Cross the road, and you should see a blue sign with the number 1 on it. Any of the paths on the right of the sign lead into the forest. There should be and information center, and small convenience store right next to the sign. The huge Seoul Forest Sign is on the other side of the forest on Gate 9. Hope this helps!

Would be better Exits 3 or 4 are closer to Seoul Forest .2min. by walk, and It's cold out side :-D