Akiyoshido Cave
秋芳洞
One of Japan's largest limestone caves, beneath the Akiyoshidai karst plateau. Walk its cool passages past Hyakumaizara, pools stacked like terraced fields.
A huge limestone cave beneath Akiyoshidai
Akiyoshido Cave is a shonyudo (a limestone cave, formed where groundwater has dissolved the rock) in Mine, Yamaguchi Prefecture. It lies beneath Akiyoshidai, a limestone plateau that spreads across the surface above, and it is designated a national Special Natural Monument.
It used to be called Takiana (waterfall cave), but it was named Akiyoshido after a visit in 1926 by the then Crown Prince, later Emperor Showa. 2026 marks exactly 100 years since it was given that name.
The entrance is a huge opening about 20m high and 8m wide, and an underground river flows out of the cave. The cave was formed over more than a million years, as groundwater dissolved the limestone, ceilings collapsed and stalactites grew.
Highlights inside the cave
The sightseeing route is about 1km long and follows a lit path. The best-known sight is Hyakumaizara (literally a hundred plates), a formation of small pools made by lime-rich water, stepped one above the other so that they look like rows of plates.
Along the way there are more features named after their shapes, such as Koganebashira (the Golden Pillar), Kasazukushi (a cluster of umbrellas), Gankutsuo and Aotenjo (the blue ceiling). The cave is also home to creatures adapted to the darkness, such as insects whose eyes have degenerated, and bats.
Three entrances and how long it takes
There are three entrances: the Main Entrance, the Kurotani Entrance and the Elevator Entrance, which takes you up onto the Akiyoshidai plateau. Allow about 60 minutes for a visit (about 90 minutes if you go there and back).
When you come out of the Elevator Entrance, the karst plateau of Akiyoshidai is right there. Seeing both the cave and the plateau lets you enjoy the limestone landscape from underground and from above.
Getting there
It is about 40 minutes by local bus from JR Shin-Yamaguchi Station. By car it is about 5 minutes from the Akiyoshidai IC.
Opening hours and fees can change with the season, so check the official website.
Tips
- The temperature inside the cave stays around 17°C all year, so it feels cool in summer and warm in winter. A light jacket is a good idea even in summer.
- If you also want to see Akiyoshidai, plan to use the Elevator Entrance to come out on top of the plateau; it makes for an efficient route.
- If you walk through one way, the exit is a long way from where you went in. Before you go in, check how you will get back to your bus or car.
Sources
Updated 29 September 2026. Opening hours and prices change, so check the official site before you go.
