One of my favorite place is Gochang in Jeollabokdo. What I like the most is the road going to Gochang.
It's a mountain where you have to climb up and down to reach Gochang so it has a zigzag road. It's really great to release stress even when you just look out of the car. The air is fresh and cool even in summer. It's a little bit dangerous but it's fun.