Juwangsan is not a high mountain. Its main peak is 720.6 metres, lower than many hills around Seoul. What makes it one of Korea's most loved parks is not height but stone: pale cliffs that rise straight out of the forest, formed from volcanic ash that settled hot, welded into rock, and was later cut by water into a narrow gorge.

The park was designated in 1976, Korea's twelfth national park. In 2017 the whole of Cheongsong County was named a UNESCO Global Geopark. You don't need to know any of that to feel it. You walk past a temple, round one bend, and the walls close in.

Most visitors only walk the valley floor. If the gorge alone feels too gentle, take the ridge: from the Sangui car park up to Jubong, the main summit, along to Hurimegi junction, then down into the gorge past Yongyeon and Yongchu falls and back to where you started. It is a loop often recommended to first-time hikers — the colour from above on the way up, the waterfalls on the way down. Allow four to five hours with stops.

The second walk is barely a walk at all. Jusanji is a small reservoir in another corner of the same park, built in 1721 to water the fields below and still used for that today. Old willows stand in the water itself, roots under the surface. Come at first light, when mist lifts off the water and the colour on the slopes behind is reflected twice.

The season is the last week of October into early November. Weekends are busy; weekdays and early mornings are not. Bring layers, start early, and eat chicken afterwards — Cheongsong cooks it two ways, both worth the drive.