InSoo-Bong is the most popular climbing area in Seoul. It is the most spectacular peak in Korea. Insubong is a large dome located in the summit area of BukHan-San ("San" means mountain in Korean)National Park.
You can reach BukHan-San within 40 minutes drive or subway from downtown Seoul and then another one hour hike to the base of the climbs. There are about 40 - 50 routes and most of them are trad climbing. The bottom half of the climbs are usually slabs and the rest is usually crack climbs. Some of the easier slabs at the lower part have extremly long run outs. Most of the climbs are 4 to 8 pitches long, so bring Friends and nuts. You will see more than 2 - 300 climbers waiting for their turn on Sunday, so start early. The view from the summit is fantastic.