Gwangju. 10km. 3hrs
Caught an ROK Air Force bus up to the top of the mountain which usually only occurs if you are actually a member of the air force. This took us up to the highest point on the mountain, about 1200m. Absolutely freezing, but spectacular views. We then descended the mountain with family and kids which made slow going before my brother in-law and I went on a detour along a trail.
Its much more rewarding to walk/run up a mountain rather than just down it. But nevertheless a bit of time on the feet and outstanding views.