Yonaguni Island And Japan’s Mysterious Sunken Megastructures

You may not think of remote mysterious islands when thinking of Japan, but many islands are a part of this diverse country. One such island is the Yonaguni Island, a charming little oasis that is home to what is considered Japan’s Atlantis. 

Yonaguni Island is one of many islands that make up the Yaeyama Islands, sitting on the western side of the cluster of islands.

While the island is small, it makes up for its size with a plethora of fun activities for tourists and locals to enjoy. 

The Mythological History Of Yonaguni Island

According to Japanese mythology, Yonaguni Island was a place visited by many gods and supernatural entities. There is a Yonaguni Ethnographic Museum located on the island to take in some of the various stories about how sacred the land is. 

One of the famous legends about the Tachigami Rock is located on Yonaguni Island. It is said that a man climbed the rock to try and make his way to the top, where he was hoping to find bird’s eggs to take and eat. However, he got stuck.

He prayed to be saved, and eventually fell asleep. He was back on the ground when he woke up. The Tachigami Rock is now considered to be a holy place on Yonaguni Island. In terms of the history of how people made their way to Yonaguni, there isn’t a lot of clearly documented history in that regard. 

The Goddess Miruku

The goddess Miruku was believed to have ruled over Yonaguni, until she was banished from the island by the god Saku.

When Saku took over, the island experienced poverty and poor living conditions. Thus, the islanders hold a festival each year to try and encourage Miruku to come back. 

San’ai Isoba

San’ai Isoba was believed to have reigned over Yonaguni Island in the fifteenth century.

This powerful woman was said to have supernatural abilities, but she also demonstrated a lot of tangible power in improving the overall conditions of Yonaguni Island.

She was responsible for establishing villages on the island, nurturing the agricultural development of the environment, and protecting her people from any potential outside threat. 

Yonaguni Monument

The Yonaguni Monument is underwater and appears to be ruins of some sort. The construction is mysterious, as no one truly knows how the ruins were built. The fascinating thing is how perfect and even the construction is. 

These mysterious sunken megastructures have baffled researchers since it was discovered in 1986 by Kihachiro Aratake.

There are about ten structures that make up this monument and it’s unclear what they were meant to be, as they are in ruin at this point. 

Some assume they could have been old temples or shrines, and some estimate that they have been underwater for at least 5000 years. 

Scuba Diving At Yonaguni Island

If you love marine life, you can have an unforgettable experience watching hammerhead sharks swim by while scuba diving in the area. You can also dive the Yonaguni Monument. 

There are different rates for scuba diving depending on your experience level. You can be provided with the equipment you need, so you don’t have to worry about bringing it yourself. 

Yonaguni Diving Services

Yonaguni Horses

Animal lovers will enjoy watching the Yonaguni horses run around on their protected terrain. These horses were once used for riding and transporting goods but have since been allowed to roam around freely throughout a few pastures dedicated to these beautiful horses. 

Yonaguni horses are typically brown and are small in stature, similar to ponies. These horses can only be found on Yonaguni Island, and it’s estimated that about 130 horses live on the island as of today. 

Yonaguni Horses

The Yonaguni Language

There is a specific language native to the Yonaguni Island, known as Yonaguni. This is estimated to be the oldest language still in existence in Japan today.

However, there are only about 400 people living on the island that are able to communicate in this language. 


Hanasake, known as flower sake, can only be enjoyed on Yonaguni Island, so it’s a must-try when you’re there.

You can find a few distilleries that make hanasake on the island that offer tastings. The alcohol is strong and some foam shaped like a flower finishes the top of the drink. 

Cape Irizaki 

Cape Irizaki is located towards the very western area of Yonaguni Island. Visiting this area in the early evening is highly recommended, as the sunset that you can view from this vantage point is incredible. There is a platform dedicated to taking in this sunset. 

In this area, you can also find a lighthouse. If you visit Cape Irizaki on a day that is clear, you can see Taiwan from the platform.

Due to where the island and its western point are located, this sunset is actually considered to be the “last” sunset that falls in Japan. 

Stone Monument of Dannu Beach in Yonaguni Island

Agarizaki Cape 

Agarizaki Cape also offers another vantage point to overlook the water, and also boasts a large lighthouse.

From the viewpoint, you can look down and see some sparkling blue water as well as coral reefs. It’s also said that you can spot many Yonaguni horses grazing in the fields below. 

The Atlas Moth 

The atlas moth is a striking, distinctive species of moth that thrives on Yonaguni Island. There is a museum dedicated to this tropical moth, and you have the opportunity to see the beautiful colorings up close. 


If you’re visiting Yonaguni Island in the summer, you will want to spend at least one day at one of their pristine beaches. The water is also safe for swimming if you need to cool off.

Dannuhama Beach is one such beach. It’s small and intimate, with soft sands sandwiched between the Yonaguni airport and Kurbura. 

Tips For Visiting Yonaguni Island

You want to ensure you have a good amount of cash when visiting Yonaguni Island. This is because there aren’t many ATMs around the island, and Japanese currency is often preferred when visiting various sites and businesses on the island. 

Depending on when you visit, it’s good to check which local businesses, such as cafes, are open at the time of your visit. This is because some local businesses will close during what they consider low season.

Yonaguni Island Location Via Google Maps

You might want to consider packing food if you visit when these places are closed. 

There are a few places you can stay on the island if you want to remain there for a couple of days, including hotels and guest houses. 

Yonaguni Accommodations Via Tripadvisor

How To Get To Yonaguni Island

The easiest way to get to Yonaguni Island is by plane. You can catch flights from Naha or Ishigaki through Ryukyu Air Commuter, and there’s a website to book tickets online. 

There are also ferries that take you to Yonaguni Island. There is a terminal in Ishigaki where you can purchase a ticket, but be sure you bring cash for your ticket.

Yonaguni Island Airport Official Website

You should get to the terminal about two hours before your ferry is scheduled to depart. 

Ferries run from Ishigaki to Yonaguni Island on Tuesdays and Fridays and depart from Yonaguni back to Ishigaki on Wednesdays and Saturdays. Be sure to research dates and times in case these dates change. 

Yonaguni Island Underwater Monuments

My fascination with Japan began several years back at a roadside bonsai stand while on vacation. I became more interested in the where and why's more than the trees themselves. My love of Bonsai led me to further research my interest in the gardens where they originated from and the places and people that surrounded those little trees. My curiosity was well rewarded upon visiting Saitama where the National Bonsai Museum was located and Omiya Village the bonsai mecca for lovers of this ancient art form. Exploring many towns and villages and even making my way to Japan's furthest southern prefecture of Okinawa. I hope to share my love of this wonderful and exotic place with all those who want to know more about Japan.