A cluster of islands floating in the middle of the West Sea, Gogunsan Archipelago is beautiful in spring and summer — but October changes everything. As the air turns cool, sea mist thickens between the islands, the tidal flats shimmer gold, and at dusk the entire archipelago sinks into sunset color. October is the one month when all three happen at once.
Daejangbong — A Viewpoint That Takes In the Whole Archipelago
If you are planning a circuit of Gogunsan Archipelago, Daejangbong is not a summit to skip. The highest point on Daejangdo — an island linked by bridge to Jangjado — it rises only 140–142 m above sea level, yet the moment you reach the top, the entire archipelago spreads out below you. Six major islands, including Sonyudo, Munyeodo, and Sinsiodo, come into view in a single glance, and that panorama is what makes this peak stand apart. CNN has featured it as a hidden gem in Asia, and the view is the reason why.
The summit is about a 20-minute climb via steep stone steps. Two paths lead up: the right-hand route toward Jangjahalmeonibawi (Grandmother Rock) is shorter but sharply graded, while the left-hand route is gentler but longer. Choose based on your fitness level, or take one path up and the other down.
Why October Is the Right Month — Sea Mist and Sunset Timing
Sea mist is common on October mornings. It fills the channels between the islands before slowly lifting — a sequence that creates an atmospheric, almost otherworldly mood unique to Gogunsan. For a clear view, plan your first climb for around midday: in spring and autumn, mist tends to roll in and out repeatedly, so very early morning or late afternoon visits risk an obscured outlook.
It is worth going up a second time at sunset. The evening light turns the island cluster gold in a way that is completely different from the midday scene. If your schedule allows, the recommended approach is two ascents — once around noon and once about 30 minutes before sunset.
Seomsitgil Trail and Tidal Flats — Walking, Watching, Staying
Leaving after Daejangbong alone would be a missed opportunity. The islands of Gogunsan Archipelago are connected by *Seomsitgil* (섬잇길), a series of pedestrian sea bridges, so you can walk from island to island. Following the bridges that link Sonyudo, Munyeodo, and Sinsiodo gives you the feeling of walking straight through the middle of the West Sea. October tidal flats take on particularly vivid color, and the landscape revealed at low tide is difficult to find anywhere else.
On Munyeodo, low tide exposes a coastal path and sea-eroded rock formations worth exploring. Sonyudo Beach, crowded in summer, becomes pleasantly quiet in October and is easy to stroll at leisure. The sunset view from below Mangjubong — known as Sonyunakjo — is ranked first among the eight scenic views of Sonyudo (Sonyu 8-gyeong), and on a clear evening it rewards anyone willing to find a spot and wait.
Getting There and Practical Tips
Gogunsan Archipelago is accessible by car via the Saemangeum Seawall. You can drive as far as Sinsiodo, then continue on foot along Seomsitgil or drive on to Sonyudo and Jangjado. The outer islands — Maldo, Myeongdo, and others — are reached by passenger ferry from Jangjado Ferry Terminal.
October weekends coincide with autumn foliage season and draw large crowds. Parking near Daejangbong is limited, so arriving in the morning is the practical move. If you want to stay overnight, Sinsiodo National Nature Recreation Forest is frequently mentioned as an option, but competition for reservations is known to be fierce — check and book well in advance. Day-trippers can eat at the cluster of restaurants around Sonyudo. For any section that crosses tidal flats, always check the tide table before you set out.
