NadeColumnar Joints: The Secret of the Hexagonal Cliffs주상절리: 육각기둥 절벽의 비밀
These perfectly hexagonal stone pillars weren't carved by anyone — they're what lava looks like when it cools slowly.
In several corners of Korea, cliffs suddenly turn geometric: thousands of stone pillars, most of them hexagonal, packed together like a giant's staircase. Koreans call them jusangjeolli, or columnar joints. Nobody carved them. When a thick flow of lava cools, it shrinks, and the shrinking cracks the rock into polygonal columns — the same physics behind Ireland's Giant's Causeway.
The most famous site is Daepo Jusangjeolli Cliff on Jeju's southern coast, where columns rise 30 to 40 meters straight out of the sea, formed by lava that flowed roughly 140,000 to 250,000 years ago. Jeju's volcanic landscape has been a UNESCO Global Geopark since 2010. Near Gyeongju, the Yangnam coast hides something rarer: columns that fan out sideways like an open folding fan, created about 20 million years ago as the East Sea itself was opening — so unusual it was designated a Natural Monument in 2012. And in Cheorwon, near the DMZ, ancient lava once flowed more than 110 km down a river channel; the resulting basalt gorges of the Hantangang River became a UNESCO Global Geopark in 2020.
Today all three sites have easy walking decks and trails, turning textbook geology into some of Korea's most photogenic coastline and river scenery.
한국의 몇몇 해안과 강가에서는 절벽이 갑자기 기하학이 된다. 수천 개의 돌기둥이, 대부분 육각형 단면으로, 거인의 계단처럼 빽빽하게 서 있다. 이것이 주상절리다. 누가 깎은 것이 아니다. 두꺼운 용암이 식으면서 수축하고, 그 수축이 바위를 다각형 기둥으로 갈라놓는다. 아일랜드의 '자이언츠 코즈웨이'와 같은 원리다.
가장 유명한 곳은 제주 서귀포의 대포 주상절리대다. 약 14만~25만 년 전 흘러내린 용암이 만든 30~40m 높이의 돌기둥이 바다에서 곧게 솟아 있다. 제주의 화산 지형은 2010년부터 유네스코 세계지질공원이다. 경주 양남 해안에는 더 희귀한 형태가 있다. 기둥이 부채처럼 옆으로 펼쳐진 '부채꼴 주상절리'로, 약 2천만 년 전 동해가 열리던 시기에 만들어졌다. 세계적으로도 드물어 2012년 천연기념물로 지정됐다. 그리고 DMZ 인근 철원에서는 옛 용암이 강길을 따라 110km 넘게 흘렀고, 그 결과 만들어진 한탄강 현무암 협곡은 2020년 유네스코 세계지질공원이 됐다.
세 곳 모두 산책 데크와 전망대가 잘 갖춰져 있어, 교과서 속 지질학이 한국에서 가장 사진이 잘 나오는 풍경이 된다.
If you go가신다면
Getting there.가는 법. Jeju: bus 600 from Jeju Airport toward Jungmun Resort (~50 min), then a short walk or taxi. Gyeongju: local bus or taxi from Gyeongju city toward Yangnam-myeon on the east coast (~50 min); pairs well with the Underwater Tomb of King Munmu nearby. Cheorwon: intercity bus from Dong Seoul Terminal to Cheorwon area, then taxi to the Hantangang trail entrances.
Tips.팁. All three sites are viewing decks and boardwalks — you look, you don't climb; stay behind the railings as the basalt edges are sharp and slippery. The Yangnam observatory and its 1.7 km coastal trail are free. At Daepo there is a small admission fee. Sea spray on windy days makes the columns most dramatic but bring a jacket.
Best time.가기 좋은 때. Year-round; clear days with some wind give the best waves against the columns. Late afternoon light flatters the Jeju cliffs.
Places in this story이야기 속 장소
- Daepo Jusangjeolli Cliff (Jungmun, Seogwipo, Jeju)
- Gyeongju Yangnam Columnar Joints & Padosori Trail (Eupcheon-ri, Yangnam-myeon)
- Hantangang River Columnar Joint Trail (Cheorwon, Gangwon)
Hidden spots nearby근처 숨은 스팟
Places locals go — not the ones on every itinerary.관광 코스 말고, 현지인이 가는 곳.
Sources (5)출처 (5)
- Daepo Jusangjeolli Cliff on Jeju's southern coast has basalt columns 30–40 m high, formed by lava flows roughly 140,000–250,000 years ago. — Visit Jeju (visitjeju.net) / Daepo Jusangjeolli Cliff visitor information
- Jeju Island has been a UNESCO Global Geopark since 2010, with the Daepo columnar joints among its geosites. — UNESCO Global Geoparks Network / Visit Jeju
- The Yangnam columnar joints near Gyeongju include a rare fan-shaped formation created in the Miocene (about 20 million years ago) during the opening of the East Sea, and were designated Natural Monument No. 536 in 2012. — https://english.visitkorea.or.kr/svc/contents/contentsView.do?vcontsId=140770
- The Hantangang River area (Cheorwon, Pocheon, Yeoncheon) became a UNESCO Global Geopark in 2020; its basalt landscape was formed by lava that flowed over 110 km along an ancient river channel. — https://www.unesco.org/en/iggp/hantangang-unesco-global-geopark
- Columnar jointing forms when cooling lava contracts and cracks into polygonal (often hexagonal) columns. — UNESCO Hantangang Geopark description / Korea National Research Institute of Cultural Heritage (e.nrich.go.kr)
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직접 가서 보세요
나들이는 이 이야기 속 장소들을 지도에 담았습니다. 진짜 가는 법, 현지 맥락, 그리고 당신의 언어로 돌아오는 답변까지.