Hallasan National Park

Hallasan is the shield volcano that built Jeju and still defines it, rising from the sea in long gentle slopes to the highest summit in South Korea. At the top sits Baengnokdam, a shallow crater lake that holds water after heavy rain and dries to a grassy bowl in between. Two trails reach the summit, from Seongpanak and Gwaneumsa, and both are long day walks on rough stone steps rather than technical climbs. Shorter routes such as Yeongsil and Eoseungsaengak reach viewpoints and turn back below the crater. The mountain makes its own weather, so cloud, wind and rain arrive fast. Azaleas colour the upper slopes in late spring, and snow covers them for much of the winter.

What you actually see

• Baengnokdam crater - the shallow summit lake in the old crater bowl.
• The summit trails - the long stone-stepped routes up from Seongpanak and Gwaneumsa.
• Yeongsil - the shorter path below the cliffs, with azaleas in late spring.
• The oreum - the small parasitic cones scattered across the mountain's flanks.

When to go

Late spring for azaleas on the upper slopes and autumn for the clearest air. The summit trails run on a reservation system with fixed entry cut-off times, so book ahead and start early. Winter brings deep snow and needs crampons. Cloud can close the view in any season, including on forecast-perfect mornings.

Honest expectations

The summit walk is long, roughly eight to ten hours return on hard stone steps, and the turnaround time stops latecomers well short of the top. Views are often swallowed by cloud, so plenty of people climb for hours and see grey. Reservations sell out in peak autumn. The shorter routes are the sensible choice for most visitors.

Nearby

The eastern oreum and the lava tubes lie below the mountain; Jeju City and Seogwipo are each under an hour away.