Overview
The whole of Jeju is this volcano; the island is its slope. Two of the seven trails reach the summit — Seongpanak and Gwaneumsa — and both require a reservation booked online, with a headcount cap and a turnaround time enforced at a checkpoint partway up. The vegetation changes with height from citrus and pine through deciduous forest to a bare alpine zone of Korean fir, and the round trip is eight to ten hours.
Highlights
Book the summit permit as soon as dates are set; they are released a month ahead and go quickly for autumn weekends. Seongpanak is longer and gentler, Gwaneumsa steeper and better looking; the classic day is up one and down the other. The lower trails, Eoseungsaengak and Yeongsil, need no permit and give the mountain in two hours.