Jeju Island is South Korea’s largest island, located off the country’s southern coast in the Korea Strait. It forms the centre of Jeju Special Self-Governing Province and is known for its volcanic landscapes, distinctive island culture, coastal scenery and protected natural areas. At the heart of the island stands Hallasan, a shield volcano and the highest mountain in South Korea.
Quick facts
- Country: Republic of Korea (South Korea)
- Administrative region: Jeju Special Self-Governing Province
- Main cities: Jeju City and Seogwipo
- Location: Off the southern coast of the Korean Peninsula
- Highest point: Hallasan, 1,947 metres
- Geological origin: Volcanic island formed over millions of years
- UNESCO designations: Biosphere Reserve (2002), World Heritage (2007), Global Geopark (2010)
- Notable cultural tradition: Haenyeo women divers
Location and geography
Jeju lies south of the Korean mainland and is separated from it by the Korea Strait. The island has an elongated, roughly oval shape, with Jeju City in the north and Seogwipo on the southern coast. Its central mountain slopes descend towards a coastline of beaches, cliffs, lava formations and small fishing communities.
Jeju’s position between the Korean Peninsula and the wider East Asian maritime region has helped shape its climate, ecosystems, settlement patterns and cultural connections. Smaller islands and islets are also administered as part of Jeju Province.
Volcanic formation and geology
Jeju is a volcanic island whose landforms developed through eruptions and lava flows over a long geological period. The island includes a central shield volcano, numerous smaller volcanic cones known locally as oreum, and extensive underground lava-tube systems. These features make Jeju an important natural area for understanding volcanic processes and landforms.
Hallasan rises to 1,947 metres above sea level. Its summit contains Baengnokdam, a crater lake, and its slopes support vegetation that changes with elevation. Around the island are hundreds of smaller volcanic cones. Basaltic lava also created caves and tubes, including the Geomunoreum lava-tube system.
Hallasan and protected natural areas
Hallasan National Park occupies the central highlands. The mountain is important for its geology, plant communities, wildlife and hiking landscapes. Its vegetation ranges from lower-elevation forests to subalpine environments near the summit. Weather can change quickly at higher elevations, so visitors should check official trail notices and seasonal restrictions before hiking.
Jeju Volcanic Island and Lava Tubes was inscribed on the UNESCO World Heritage List in 2007. The property includes Hallasan Natural Reserve, Seongsan Ilchulbong Tuff Cone and the Geomunoreum lava-tube system. The island was also designated a UNESCO Biosphere Reserve in 2002 and a UNESCO Global Geopark in 2010. These are distinct international designations recognising biodiversity, geological heritage and sustainable development.
Climate and ecosystems
Surrounded by sea and influenced by regional ocean currents, Jeju generally has a milder maritime climate than many inland parts of the Korean Peninsula. Conditions vary with altitude and season: the coast and central mountain can experience very different temperatures and weather on the same day. Rainfall, wind and fog are important features of the island environment.
The island contains several ecological zones, including alpine and subalpine vegetation, temperate forests, grasslands, wetlands and coastal and marine habitats. Its protected areas provide habitat for native plants and animals, including species adapted to the island’s varied elevations and volcanic terrain.
Administrative areas and settlements
Jeju Special Self-Governing Province is organised around two principal cities: Jeju City and Seogwipo. Jeju City is the main urban and administrative centre in the north and is home to the island’s principal airport and port facilities. Seogwipo occupies the southern part of the island and is associated with coastal landscapes, agricultural districts and access to southern attractions.
Outside the main urban areas, villages and smaller settlements are distributed around the coast and across the island’s agricultural interior. Roads connect the coastal communities with the central mountain region, while public buses and intercity services provide alternatives to private vehicles.
People, culture and traditions
Jeju has a distinctive local culture shaped by its island geography, history and relative separation from the mainland. The Jeju language and dialect traditions, local foodways, stone walls, village shrines and maritime customs form part of its cultural heritage.
One of the island’s best-known traditions is that of the haenyeo, women who dive to collect seafood such as shellfish and seaweed, traditionally without breathing equipment. Their knowledge of tides, seasons and marine resources has been passed between generations. The haenyeo tradition is recognised by UNESCO as intangible cultural heritage and is closely connected with community identity and the sustainable use of coastal resources.
Economy
Tourism is a major part of Jeju’s economy, supported by its volcanic scenery, beaches, hiking routes, cultural sites and visitor facilities. Agriculture is also important; the island is known for citrus cultivation, including mandarins, as well as other subtropical and temperate crops. Fisheries and aquaculture remain connected to coastal communities and the haenyeo tradition.
Jeju’s natural environment is both an economic asset and a conservation responsibility. Tourism and development create employment, but they also require planning to protect water resources, landscapes, habitats and local communities.
Landmarks and places of interest
- Hallasan National Park: Protected mountain landscapes, hiking routes and the Baengnokdam crater lake.
- Seongsan Ilchulbong: A volcanic tuff cone on the eastern coast, known for its distinctive crater and sunrise views.
- Geomunoreum lava tubes: Part of the island’s internationally recognised volcanic heritage.
- Jeju Olle Trail: A network of walking routes that follows coastal and rural landscapes.
- Udo: A smaller island off Jeju’s eastern coast with coastal scenery and local communities.
- Seongeup Folk Village: A settlement where traditional houses, stone walls and cultural features are preserved.
Frequently asked questions
Where is Jeju Island?
Jeju Island is off the southern coast of South Korea, in the Korea Strait. It is the main island of Jeju Special Self-Governing Province.
Is Jeju Island volcanic?
Yes. Jeju was formed by volcanic activity and contains Hallasan, many smaller volcanic cones and extensive lava tubes.
What is the highest mountain on Jeju Island?
Hallasan is the highest point on the island and in South Korea, reaching 1,947 metres above sea level.
Why is Jeju Island important to UNESCO?
Jeju has separate UNESCO recognitions as a Biosphere Reserve, a World Heritage property for its volcanic island and lava tubes, and a Global Geopark.
References
- UNESCO, Jeju Island Biosphere Reserve — ecological characteristics, location and cultural context.
- UNESCO, Jeju Island UNESCO Global Geopark — volcanic landforms, oreum, Hallasan and geological heritage.
- Korea Tourism Organization, Natural Heritage Sites — World Heritage components and Hallasan.
- Invest Korea, Jeju: Pristine Natural Environment — island geography, volcanic cones and lava tubes.
- National Atlas of Korea, Jeju Special Self-Governing Province — island geography and administrative context.