두꺼운 용암이 급격히 식으며 만들어진 육각형 모양의 현무암 주상절리대다. 높이 30m, 길이 1km의 주상절리대로 국내에서 가장 큰 규모를 자랑한다.
It is a hexagon-shaped basalt columnar joint formed when thick lava cools rapidly. At 30m high and 1km long, it is the largest columnar joint in Korea.
A columnar basalt jointing area formed by thick lava cooling rapidly, shaped like hexagons. It boasts the largest scale in Korea with a height of 30 meters and length of 1 kilometer.