OK, looking at Google maps, that Taebaek City circuit looks promising. There's a long twisty mountain road (31) on the way to the track. Its probably another 30-45min ride east from Wonju. So 2 hours total with no traffic. Probably a nightmarish 4+ hour ride w/ traffic.
Oh, Taebak city looks like a somewhat cool place to visit. Skiing, rafting, and sightseeing without overcrowding and polluted air? Hopefully the rafting water isn't like the Han river.
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