Explore the Great Plateaus and Caves of Yamaguchi

Yamaguchi Prefecture is full of natural splendors, such as caves and plateaus.

Visitors to Akiyoshidai Plateau in Yamaguchi have the chance to experience some of Japan's greatest natural wonders. You'll be in awe while exploring ancient formations that are both above and below ground. The park is known for its three breathtaking caves that feature remarkable sights like underground lakes and waterfalls. Be sure to take a geotour through the park itself, where a local can enrich you with their first-hand knowledge of the area.

Akiyoshidai Plateau: Walk through an ancient coral reef

Akiyoshidai Plateau is an area filled with unique geological features formed mostly from Paleozoic limestone. The area was under the ocean 300 million years ago and contained a coral reef. These lands eventually eroded due to rainfall, leaving behind the karst formations that you see today. The plateau sits between 500-600m high mountains while the surface of the plateau itself is between 180-420m above sea level. The landscape is a sight to behold.

Every February, the landscape is drastically altered by the residents. The event, called Akiyoshidai Yama-yaki, is a controlled burn of all of the dried grass on the plateau. Once it is all burned, your view changes dramatically. The bright white stones all stand out against the charred landscape.

In addition to walking and cycling, you can enjoy the scenic white limestone and rolling hills of the landscape by joining a 90-minute Segway tour held in both the morning and afternoon, or by riding in a comfortable seven-seat tuk-tuk.

In the Akiyoshidai area, an application for UNESCO Global Geopark designation was submitted in November 2024, and official recognition is expected in the spring of 2026.

How to get to Akiyoshidai Plateau: You can get to the plateau by car or bus from Yamaguchi. The JR Bus runs a few times a day from Shin-Yamaguchi Station to Akiyoshidai Plateau. If you are driving, it takes around 45 minutes. Start on highway E2 and continue to highway E2A, then take highway 490, followed by highway 435 to the plateau. 

• Address: Mine City, Yamaguchi 754-0511

Segway Tour

Meeting Place: Chojagamori Parking Lot, Mito-cho, Mine City, Yamaguchi Prefecture
Business Hours: 8:30 a.m. to 5:30 p.m. daily (March to November), 8:30 a.m. to 4:30 p.m. (December to January)  ※Tours are cancelled during winter season.
Contact: Akiyoshido Information Center  TEL: +81-837-62-0018
Access: About 40 minutes by car from Shin-Yamaguchi Station to Chojagamori Parking Lot. About 50 minutes by car from Yamaguchi Ube Airport.

Tuk-Tuk Rental

Address: 3506-2 Akiyoshi, Shuho-cho, Mine City, Yamaguchi Prefecture 754-0511
Business Hours: 9 a.m. to 5 p.m. daily
Contact: Mine City Tourism Association  TEL: +81-837-62-0115
Access: About 40 minutes by bus from Shin-Yamaguchi Station to the Akiyoshido Bus Stop. It takes about 60 minutes by bus from Yamaguchi Station. About 50 minutes by car from Yamaguchi Ube Airport.

Akiyoshido Cave: Japan's largest stalactite cave

Underneath the Akiyoshidai Plateau, you can find a 300 million-year-old cave called Akiyoshido Cave. You'll have no problem exploring this cave as it has paved walkways, steps, and plenty of lighting. While you are spelunking down the cavern, keep your eyes peeled for all of the stalactites, which are some of the largest in Japan. They'll be hanging from the ceiling, which averages around 40m high, but can reach 80m at its peak. Another amazing feature of the cave is a large underground lake that feeds a waterfall, both of which are bright blue. 

There are three different ways to enter the cave: through Akiyoshido, through Kurotani, or through an elevator. One thing to note is that this cave stays around 17°C all year long, so you may need a light jacket if you get cold easily. Be sure to pack some extra water as well. 

For those seeking even more adventure, there is a special course leading to the underground river deep inside the cave, accessible through an unpaved and unlit area that is usually closed to the public. Here, you can view precious rock formations that have been shaped over thousands of years.

Guided tours led by experienced teams are available for groups of up to six people and last between two to four hours. Courses are tailored to various skill levels, so both beginners and experienced explorers can find an option that suits them.

How big is Akiyoshido Cave?

Akiyoshido Cave is around 11km long, making it the longest limestone cave in all of Japan. The portion that visitors can explore is around 1km long, and you can make it through in under an hour.

How to get to Akiyoshido Cave: If you rent a car at the Yamaguchi-Ube Airport, just drive on highway E2 to highway E2A, then take highway 490, followed by highway 435 to the park center. You'll be there in about 60 minutes—just look for signs for the cave. JR Bus runs a route every few hours between Shin-Yamaguchi Station and Akiyoshido Bus Center if you don't have a car. 

• Address: 3449-1 Shuho-cho Akiyoshi, Mine City, Yamaguchi 754-0511

Optional activity: Akiyoshidai/Akiyoshido GEO Guide Tour

What better way to take in the Akiyoshi Plateau and Akiyoshido Cave than by taking a geoguided tour? These tours will let you learn the history of the area and its geology, natural sights, and residents. Geoguides, who are mostly residents of the area, lead these tours. They know every little detail of what you'll encounter. An English interpreter will accompany you as well, so you won't miss a thing. 

There are numerous options to choose from depending on your fitness level and how much free time you have. The exact path of the course is up to the guide themselves.

• Akiyoshidai Enjoyment Courses - 1 or 2-hour walking courses that take you through scenic areas like Kitayama, Dorine Field, and Managagatake.
• Cave Exploration Courses -Each of these 1.5 and 2-hour courses takes you underground into one of the three caves in the area: Akiyoshido, Kagekiyodo, and Taishodo.
• Karst Plateau Course - Learn how the karst formations at Akiyoshidai and Akiyoshido transformed over the years.
• Life-Orientated Courses - Take a look at the culture, customs, and lifestyle of the residents of Akiyoshidai on this tour.
• White, Black, and Red Course - Experience the three miracles of the geopark: Sakurayama, the Momo tree excavation site, and the Nagato copper mine site.

How to get to the Mine City Tourism Association: You can get to the geopark by car from the Yamaguchi-Ube Airport in about 45 minutes by taking highway E2 to highway E2A, then take highway 490, followed by highway 435 to the park center. If you want to take a bus, JR Bus runs every few hours between Shin-Yamaguchi Station and Akiyoshido. 

• Address: 3506-2 Akiyoshi, Shuho-cho, Mine City, Yamaguchi 754-0511

Optional activity: Kagekiyodo - Cave Exploration Tour

Kagekiyodo Cave got its name from general Kagekiyo, out of the samurai lore. Legend has it that around 800 years ago, he lost at the battle of Dan-no-Ura and had to retreat into this cave. When you first enter the cave, the patterns and designs on the ceilings and walls that nature has created will amaze you. Once you are able to take a closer look, you'll realize that these patterns are full of fossils like coral, seaweed, and shells.

Adventure deep into the Kagekiyodo Cave

If you want to see more of the cave, you can go on the adventure course. Before you depart for this cave tour, you'll receive a helmet, rubber boots, and a flashlight because you'll be going into the deepest, darkest parts of the cave. The adventure course takes around an hour to complete.

How to get to Kagekiyodo Cave: It takes about an hour to reach Kagekiyodo Cave by car from the Yamaguchi-Ube Airport by taking highway E2 to highway E2A, then taking highway 490, followed by highway 28 to your destination. If you prefer the bus, JR Bus runs a bus every few hours between Shin-Yamaguchi Station and Akiyoshido.

• Address: 3248 Aka, Mito-cho, Mine City, Yamaguchi 754-0302

Multi-Level Taishodo Cave: Journey from Heaven to Hell

The third cave located in Akiyoshidai Plateau is Taishodo Cave. Legend has it that this cave was where local villagers would hide away their cows in periods of war. This cave was only discovered in 1921 and consists of five different levels that you can explore. They range from the higher heavenly named floors all the way down to Hell itself at the lowest floor. You can cross an awe-inspiring natural limestone bridge and see sights like "Wobbly Road," "Lion Rock," and "The Entrance to Hell." 

How to get to Taishodo Cave: It takes 45 minutes to get to the cave from the Yamaguchi-Ube Airport by taking the E2 to E2A, followed by 490, 28, 239, and 242. There is also a JR Bus from Shin-Yamaguchi Station to Akiyoshido. Then you can take a bus that runs between the three caves.

• Address: 2659-4 Aka, Mito-cho, Mine City, Yamaguchi 754-0302

What is the best cave to visit?

Each cave has its own unique features, which means you'll have to visit them all to decide which is the best. Whether it's spelunking through massive stalactites in Akiyoshido, admiring nature's own artwork in the darkness of Kagekiyodo, or exploring both Heaven and Hell in Taishodo, you'll make memories of a lifetime. Once you're ready to take in the natural beauty of Yamaguchi, both above and below ground, all you need to do is book a flight to the Yamaguchi-Ube Airport on Japan Airlines. 

The JAL Japan Explorer Pass allows travelers to fly affordably to over 30 cities on JAL's domestic network. JAL offers free wifi on domestic flights in economy class.