Jusangjeolli Cliffs

The geologically extraordinary columnar joints along the Jusangjeolli Cliffs on the Daepo Coast of southern Jeju Island, Korea, are the result of rapidly cooling lava of volcanic, basalt flows dating back to 25,000 years ago.  Molten lava contracts during cooling, splitting the rock into columns typically having five to six sides.  The resulting symmetry has more of a man-made than a naturally occurring appearance.

The Giant's Causeway in Northern Ireland and northeastern Wyoming's Devils Tower are other well-known examples of the columnar jointing phenomenon.

Columnar jointing along Jeju Island's south
coast near Jungmun.

Looking west toward Mt. Sanbangsan
from a viewing platform
atop the Jusangjeolli Cliffs.

Looking down on the cooling cracks
of a basalt flow.

An inlet along the cliffs.

Viewing platform (upper left) at the popular, much visited
Jusangjeolli Cliffs.