Ieodo isn't a livable island — it's an ocean research station built atop a reef submerged 149km southwest of Marado. Because roughly 60% of typhoons that make landfall in Korea pass near here, it holds special meteorological significance as the front line for observing them first.
Ieodo is a submerged reef that never breaks the surface, with its shallowest point about 4.6m underwater. In 2003, Korea built the Ieodo Ocean Research Station atop this reef using stilt-like structures — the country's first comprehensive ocean research station, conducting integrated ocean, weather, and environmental observation.
Roughly 60% of typhoons making landfall in Korea pass near Ieodo. The station can observe a typhoon directly 8-12 hours before it reaches the Korean peninsula, playing an important role in early warnings and forecast accuracy.
Ieodo never breaks the surface — it stays submerged at all times. The name often leads people to assume it's an island, but what's actually there is an unmanned observation station built on stilts anchored to the reef.
As Korea's first comprehensive ocean research station, it monitors wave height, water temperature, wind direction, and wind speed in real time — the first point to catch weather changes in the open sea south of Jeju.
In summer and autumn, typhoons frequently pass near here, and the station's readings feed directly into real-time typhoon forecasts. Winter brings frequent high waves typical of the open sea, driven by the northwest monsoon, and spring is a corridor for air-quality changes arriving from the direction of China. For general season-by-season tips, see the seasonal outdoor guide.
You can't visit Ieodo's unmanned station in person, but when a typhoon is moving north over the South Sea, checking readings from this spot can help you gauge its track and intensity well before it reaches the Korean peninsula. For general threshold-by-threshold guidance on UV, feels-like temperature, and fine dust, see what to do.
No one actually lives at Ieodo, but searching for and adding "Ieodo" in sanCheck lets you watch this spot's weather side by side with your other saved places as a typhoon approaches over the South Sea.