Seoraksan is spectacular in all seasons, but the timing affects both the experience and the crowd levels dramatically. Autumn — specifically the last two weeks of October — draws the largest crowds in the park's history, as the maple and oak forest turns brilliant red and gold against the grey granite. The foliage is extraordinary, but the park entrance, cable car, and main trails become genuinely packed. Book accommodation far in advance for this period.
Spring (May–June) is the next best time: wildflowers on the higher ridges, pleasant temperatures, and far fewer visitors than autumn. Summer (July–August) brings heavy rainfall and humidity but the waterfalls are at their most powerful and the forest is intensely green. The summit area requires climbing permits in summer due to the high number of hikers. Winter (December–March) offers the park at its most dramatic and most solitary — snow on the granite peaks, ice on the trails, and very few other walkers. Many sections of trail close due to ice in deep winter; check conditions before hiking.