Akiyoshi Cave is one of the largest limestone caves in the world located about 100 m under Akiyoshidai limestone plateau in the western part of Yamaguchi Prefecture. Of the 10 kilometer long limestone caves, 1 kilometer is open to the public as a sightseeing course. The cave features an array of intricately shaped caves, including the 15 meter-high “Golden Column” and “100 plates.”.