October is a great month for climbing all over the peninsula. With two weeks you'll have time to explore. Will you be camping? There's just so much climbing in Korea, you can go pretty much anywhere. There's climbing in and around the big cities. . . or you can head out to rural areas. Seonunsan and Daedunsan are beautiful in Autumn. But so is the whole country.
"If you can't do something well, you might as well learn to enjoy doing it poorly."
-- from a de-motivational poster, but I find it oddly liberating