
Karst pinnacles at Akiyoshidai.
The 'Akiyoshi plateau' or , is a 130 square kilometre area of
karst topography in
Yamaguchi Prefecture at the extreme western end of
Honshū island,
Japan. Much of the area was protected as a Quasi National Park in 1955, and a portion is a Special Natural Monument.
Akiyoshidai is served by a natural history museum, visitor centre, resthouse, youth hostel and park headquarters building, and is traversed by a scenic roadway and several walking trails. Events include a fireworks festival in July, a Karst Walk in November, and an annual burning off of dry grasses in February called Yamayaki.
Geology
Uplifted reef
limestones of
Paleozoic age were thickened by
overfolding during the Akiyoshi orogenic movement. Subsequent erosion has created an undulating
karst landscape dimpled with many
dolines and countless limestone pinnacles up to 2m in height. Beneath the surface lie hundreds of
caves, a few of them quite significant. Fossils of
Pleistocene age include the Japanese rhinoceros,
Stegodont elephant and Young tiger, and numerous animals from the last interglacial period.
Akiyoshi-do

Entrance to Akiyoshi-do cave.
Towards the southern end of Akiyoshidai is the
cave Akiyoshi-do, named by Japan's former emperor in 1925 when he was Crown Prince. This spacious cave is up to 100 meters wide and has 8.7 kilometers of passages, making it the second-longest in Japan. Much of it is accessible to tourists along a walkway and bridge system, entering at the cave's lowest point and exiting via an artificial elevator. This portion of the cave is well decorated with a variety of large and colorful
speleothems.
References
''Akiyoshi Plateau and Akiyoshi Cave'' information pamphlet
External links
★
Akiyoshidai Natural History Museum website
★
Caves of Akiyoshidai