Deogyusan is the fourth-highest mountain in South Korea and covers 232 km² across the border between North Jeolla and South Gyeongsang. It became a national park in 1975 — and the ski resort on its northern flank predates that designation, which is why a national park has a gondola, hotels and pistes inside it.
However you feel about that, the practical effect is real: Deogyusan is the only place in Korea where someone who cannot walk up a mountain can stand on a 1,600m summit in winter and see the rime ice for themselves. The gondola climbs to Seolcheonbong at 1,520m and the walk from there to Hyangjeokbong is short and gentle.
The other half of the park is Gucheondong, the long valley on the Muju side, which Korean tradition divides into thirty-three named scenes — Inwoldam, Waryongdam, the Gucheon falls and so on, each with its own story. It is a flat walk beside water for as long as you want to make it.
Muju itself is worth knowing about for the firefly festival, held each September; the valleys here are clean enough to still have them in numbers, which is rare.