A cave is defined here as a large hole in the side of a mountain or sea cliff OR underground OR undersea.

1. Gyokusen-do Cave in Okinawa What’s stellar about this cave? It has over 200,000 beautifully formed stalactites. The cave is 3 miles long. Pay a virtual visit or one in person. Access info: 1336 Maekawa Tamagusuku-son, Okinawa Phone: 098-949-7421)

2. The Ikura-do Cave in Okayama. Perched on along a 240-meter tall vertical precipice, this cave was formed by slow erosion of the limestone (over a very long time) by the Takahashi-gawa River. The Kusama Karst Tableland extends upstream of the river that has also carved out a beautiful gorge called Ikura-kyo. The cave is 1,200 meters long but fortunately, you won’t have walk the entire length…there’s a short walking course. You’ll be starstruck by the series of glittering stalactites (To get there: Fly an hour 20 minutes from Tokyo Haneda Airport to Okayama Airport or take the JR Tokaido and Sanyo Shinkansen Line from Tokyo Station to Okayama Station. Then, take the JR Hakubi Line to Ikura Station. It takes 4 hours 30 minutes.)

3. Ryusen-do Cave in eastern Iwate. Batman’s cave may well be here. One of the two best-known tributary caves is named Komori-ana (Bat’s Cave) – the other cave is called Tortoise Rock Cave. There are five different unique species of bats living in the cave with each species listed as a natural monument. Besides that distinction, Ryusen-do, situated in the foothills of Mt. Ureira in eastern Iwate, is one of the three largest limestone caves in Japan. Nobody has explored its full length so nobody knows exactly how long the cave is. But 2,500 m of it HAS been explored, with maybe another estimated 5,000 m to be explored. That’s not all, the cave is also world famous for clarity and depth of several of its underground lakes. The deepest pool in Japan at 120 m is found here. One of its lakes glows a mysterious and eerie emerald green. Spring water flows from the deepest back part of the cave into the lakes. It is listed as a natural monument. Also worth a quick visit is the nearby but smaller Ryusen Shindo cave that now serves as a science museum with displays and explanations of the history of the caves’ exploration, the geological features and life-forms found here. Access: To get there, you need to ride the JR Tohoku Shinkansen (hurray) from Tokyo Station for two and a half hours to Morioka Station, AND THEN hop on a bus for two and a half hours all the way to the Ryusen-do-mae bus stop.

4. Ryugado Cave in Kochi prefecture, Shikoku. This cave is one of the three major stalactite caves and one of the biggest caves in Japan, and perhaps oldest, about 150,000,000 years old. What to watch out for: magnificent limestone pillars and over 20 waterfalls of various sizes all lit up for tourists like you! Get ready for an underground adventure – but no Lord Voldemort or the Snake of Slytherin in sight here, maybe just archaeological relics from the Yayoi Period roughly 300 B.C. — 300 A.D. Access: Make your way via one of 3 bridges from the mainland to Kochi city in Shikoku. About 24 km from Kochi, take the train to Tosayamada, and then take the taxi or cave bus to the cave site. If driving, take the Ryugado Skyline, a windy route with spectacular coastal views.

5. Akiyoshidai Cave in Yamaguchi prefecture. The cave is part of a largest complex of limestone caves and the largest karstland or karst plateau (130 square kilometers) in Japan. 420 caves have been discovered! What’s even more fascinating about this place is that the limestone rocks of the Akiyoshidai plateau began as a coral reef in the ocean about 350 million years ago. Over the course of 130 million years, volcanoes erupted on the ocean floor and upheavals caused by movements of the earth’s plates resulted in parts of the earth’s rocks being turned over and folded over. As the rocks folded over, the lower older layers of the coral reef came to the surface forming the Akiyoshidai plateau. This is said to be a great place for fossil-hunting. The main element in limestone rock is acidic calcium. Rainwater carrying carbon dioxide will penetrate into the ground and caves, dissolve the rock and forming calcium carbonate. By this process, the limestone rock is gradually eaten away or eroded with holes and crevices gradually forming the huge limestone caves that we have been talking about, over the millions of years, of course. Many are taken by this site but a reviewer says the Okinawa ones are much more spectacular. See especially the information and pictures here and here.

6. Ryugashido Limestone Cave in Shizuoka prefecture A big cave on the south slope of Mt. Ryugashi, dating to 250 million years ago. Only 400m of 1,000m-length cave is open. Visit it for its large underground waterfall (with a 30-m drop) and many limestone features. Access: Make for the JR Hamamatsu station at the north exit, go to the bus terminal track 15 and take the bus bound for “Okuyama” (50 minutes) and the “Ryugashido Iriguchi” bus stop. Walk for 5 minutes.

7. Genbudo Cave A famous geological formation of Japan, the attraction consists of three caves with thousands of basalt pillars. The cave is part of the Sanin Kaigan National Park, which consists of a 75km long seacoast of granite and basalt. Erosion has resulted in 91 large and small islands and reefs, as well as 52 caves and arches, such as those seen at Genbudo and Yoroi-no-Sode. Access: The park is located in western Honshu as a continuous 75km long sea coast between Amino (Kyota prefecture) and the sand dunes near Tottori prefecture. Genbudo is located east of the Maruyama River on the road between Toyo-oka and Kinasaki on the Japan Sea side of Hyogo Prefecture.

8. Ama no Iwato (lit. the “heavenly rock door”), 8km north-east from Takachiho gorge in Kyushu, is said to be where the sungoddess Amaterasu hid herself in a cave so that the world was plunged into darkness. The Yasugawara Cave is where Amaterasu is said to have hidden, is a few hundred meters away from the shrine Ama no Iwato-jinja Shrine up the Iwato-gawa river. “The cave is not deep and is the setting of a shrine where it is said that the Japanese sun goddess hid until she could be convinced to come out. It is lovely next to a picture-perfect stream.” – comments by Andrew Taber. Access: The nearest airport is Miyazaki, almost 3 hours away by train, via Nobeoka. The best way to get there is really to rent a car. Getting to Takachiho can be a tough trip. The train ride cost about ¥3,200, using the JR Limited Express Nichirin, then the Takachiho Railway from Nobeoka. Fukuoka or Beppu, you can use the same JR Limited Express Nichirin line to Nobeoka (4h10 and ¥5,800 from Hakata, 2h20 and ¥2,400 from Beppu), then the Takachiho Railway 90 minutes to Takachiho. (From Kumamoto, take the 60-km road that links Takachiho and Kumamoto, or a train to Oita, then to Nobeoka). Take a bus or taxi from Takachiho station to avoid walking the 8km).
References: Amaterasu in the Kojiki text; Yokugura performances in Takachiho; Takachiho Guide, Japan Reference

9. Caves in Gifu prefecture, especially in the Hida area, near Takayama. “There are several terrific caves with waterfalls and limestone formations.” – comments by Andrew Taber. Visit 3 together on a field trip:

Hida daishonyu-do, Nyuukawa-mura. Access: Hida Cave Management Office, Tel: 0577-79-2211, Fax: 0577-79-2643 Take the JR “Takayama” line from the Shinkansen Nagoya station (2 hours 10 minutes) to Takayama station. From the station, take the bus via “New Hodaka Onsen” way (28 minutes) Get off at “Shonyudou Guchi” and walk for 1 km. Map and cave details here.
– Ootaki shounyu-do, Hachiman-cho. Access info here.
Sekigahara daishonyu-do, Sekigahara-tyo. Access: Take the JR Tokaido line to Sekigahara station and walk for 80 minutes (4km). If driving, from the Meishin expressway Sekigahara IC turn into Route 365 on your left. Turn left at the traffic signal and junction between the Mt Ibuki motorway entrance and the crossing of Route 21 bypass left. Proceed for about 5 minutes to cave.
Jomon shonyu-do and Miyama shonyu-do, Hachiman-cho. Access info here.
The JR Tokaido Main Line runs through Gifu on its way from Nagoya to Kyoto and Osaka. From Tokyo Station, the best way to reach central Gifu is to take a Tokaido Shinkansen train (Nozomi or Hikari) to Nagoya, then change to a Tokaido Line local train for the run to Gifu. (2 1/4 hours; 11,190 yen via Nozomi, 10,990 yen via Hikari). The same connection can be made coming from Kyoto and Osaka in Kansai, and from other stations on the shinkansen network to the west. By car, take the central Chūō Expressway, which largely follows the alignment of the Tokaido Line, also passes through southern Gifu.

10. Shizushi Limestone Cave Park, Mizuho Town, located in the center of Kyoto Prefecture. The only one of its kind in Kyoto Prefecture, the cave with four main sections, is 52.5 meters long, 4 wide and 25 deep. The vertical cave has stairs that go straight down. Limestone formations only grow 6 mm in a hundred years. Attractions: The Golden Pillar formation (2 m around and 5 m long), among others. There is a campground (with full facilities) nearby. Access: Take the JR San-in Line from Kyoto Stn. to Sonobe Station and then a JR Bus to Hiyama (about 30 min.). From Hiyama take a town bus Shonyudo-guchi Stop (about 15 min.). Phone: 0771-86-7125.

Other notable caves:

Kaza-Ana or Windy Hole Cave in O’hasama Town, Iwate Prefecture. Animal bones ca 10,000 years ago or earlier have been found at the limestone cave located approximately 12 meters above present riverbed level, and 1 meter in width and 10 meters in length. Access: Kaza-ana Cave is situated in west end of Kitakami highlands and along Yagimakigawa River which joins Kitakamigawa River. See map info here.

Fukui & Shiga prefectures have some caves that are archaeologically significant. Visit:
Hakuba-do in Waizumi-mura, Fukui prefecture. Note: A number of caves are landmarks for significant archaeological discoveries. More info here.
Kawachi fuuketsu, in Taga-cho in Shiga prefecture.

For info on showcaves other than those listed above, visit these web pages for a fuller listing here and here.

Sea Caves:

Anatoshiiso Rock with Three Giant Holes, Massaki-cho, Oofunato-shi (near Kamakura), Kanagawa Anatoshiiso is the work of countless years of wild waves and stormy winds eroding the rock. But having three giant holes in one rock is truly unique. On calm days, small pleasure boats can sail through the holes as a tunnel. Access, photos and info here.

Enoshima Cave. Enoshima island is particularly famous for its legend of the dragon that lives in the caves beneath the island. Not a cave to rave about though, visit it like the rest of usual tourist crowd for the ancient legendary hype. The cave visit is usually made as an accompaniment to other attractions on the island or in the area. See a picture of interior of cave here. Access info: From Kamakura, you can take the private Enoden line west of Kamakura station (about 20 minutes). Access to the island is via a 600-m long bridge.

The Tensohodo, at Dogashima, Nishiizu (West Izu) is a large sea cave. Take a 20-minute boat ride out to see the cave which has a sky-roof . The interplay of light and shadow makes beautiful patterns on the water. Visitors come to the area for the picturesque limestone outcrops but also for the good beaches and snorkeling in the clear water. More info here. Access: Take one of the tour boats that depart from the jetty in front of the main car park.


A list of the 69 longest caves in Japan (containing a few hyperlinks) here.

A list of Japan’s deepest caves in Japan here.

Speleological Society of Japan’s list of sites for horizontal-caving here

Speleological Society of Japan’s list of sites for vertical-caving here

An article on how to make a snow-cave, Japan’s Back Country Snow World.

Speleological Society of Japan, an academic organization concerned with conservation, exploration and safety standards. Probably the best website on caving in Japan.

Speleological Survey Group of Yamaguchi University, (web info in English) It had its beginnings in 1960 in the activities of an earth science classroom of the Department of Education of Yamaguchi University led by Prof. M. Kawano. Main investigations have been conducted in Akiyoshi-dai (limestone area), as well as in caves distributed in Gifu, Hiroshima, Fukuoka and Kagoshima. See the group’s useful website with many good pictures.

Tokyo Speleo Club
(website in English and Japanese). Might be a good network to join for spelunking activities if you live in the area.

Mt Fuji Vulcanospeleological Society Interesting because of its focus – as the only one organization concerning with Vulcano-speleology in Japan (since 1970). It has a small photo-gallery.

Edogawa Cave Club
(in English and Japanese) has its roots in the Edogawa High School Geological Club