Visiting Asia’s Longest Lava Tube
The cave is located on Jeju, the largest island in South Korea, which itself was formed by volcanic activity.
A UNESCO Heritage Site, one kilometer (just over half a mile) of the 13.4 kilometer (8.3 mile) long lava tube is open to the public.
The 40 minute long tour culminates with a view of a 7.8 meter (25.6 feet) high lava column, created when lava dripped from a hole in the ceiling, the tallest lava column on Earth.
Exploring Asia’s Longest Lava Tube [National Geographic News]