Seto Inland Sea

The Seto Inland Sea lies between three of the four main islands of Japan (Honshu, Shikoku and Kyushu), extending roughly 450 km east to west and anywhere from 15 km to 55 km south to north. This region, which is often referred to as Setouchi in Japanese, is noted for its scenic beauty. Islands lie scattered across the sea’s tranquil waters, white sandy beaches rim its shores, pine groves provide welcome shade, and rice paddies terrace the hillsides. The first Westerners to gaze upon the area after it was opened in the mid-nineteenth century, including Thomas Cook and Philipp Franz von Siebold, praised its charms in their travelogues. In 1934, the section of the Inland Sea bordered by Kagawa, Okayama and Hiroshima prefectures became Japan’s first national park.

Since ancient times, the Seto Inland Sea has served as a strategic shipping route, carrying not only goods but also peoples and cultures to and from the Kansai area. The islands and coastal regions welcomed this influx of knowledge while, at the same time, developing their own unique culture and traditions. The fact that the region was formed through the workings of both man and nature is one of its many charms.

During the 1960s, Japan underwent rapid economic growth, but the development of large scale industries in the Setouchi region exacted a heavy toll in the form of environmental pollution. The rich historical and cultural legacy of the Seto Inland Sea thus reflects both the positive and negative aspects of humankind’s interaction with the natural environment.


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Naoshima covers an area of 8 square kilometers and has a population of about 3,100. Emperor Sutoku (1119-1164) gave the island its name when he was exiled to this area in 1156. The name literally means “gentle island” and reflects how impressed the emperor was by the islanders’ sincerity.

Situated on a strategic trade route, the island developed a powerful navy under the ruling clan in the 15th century. Subsequently, many islanders engaged in the lucrative marine cargo trade.

Theater arts blossomed during the 19th and early 20th centuries, a legacy that remains in the form of Naoshima Onna Bunraku, a female-only puppet theater. Fishing, another core industry, remains strong, and yellowtail and seaweed farming continue to support the island’s economy along with a metal refinery on the island’s northern tip.

Today, Naoshima is internationally known as a focal point for contemporary art with museums designed by Tadao Ando and site specific works by such artists as James Turrell, Walter De Maria and Hiroshi Senju.



Home to the Teshima Art Museum and a popular destination for those seeking a different side of Japan, Teshima is located between Naoshima and Shodoshima and has a population of about 800 people. The island has been inhabited for at least 9,000 years, and the oldest shell midden in Western Japan is located on its southernmost tip.

Teshima prospered along with the flourishing of the Seto Inland Sea trade route. Stone quarrying was the island’s primary industry for a thousand years until quite recently, and Teshima stone was used widely throughout Western Japan, including for the stone lanterns at Katsura Imperial Villa in Kyoto.

The island is also blessed with a plentiful supply of spring water for irrigation. In the past, it produced enough rice for export to other areas of Japan. Rice terraces still cover the island’s lower slopes while thick woods rise up the small mountain known as Danyama in the island’s center. Dairy farming flourished from the mid-nineteenth century. The plentiful supply of milk was one reason an orphanage was established here immediately after World War II to care for Japan’s many war orphans.

More recently, Teshima was the site of Japan’s worst case of illegal industrial waste dumping. This scandal forced the nation to make environmental issues a top priority. As a result, policies concerning waste disposal were revised and stricter environmental standards were enacted.



The closest island to Takamatsu, Megijima has an area of less than 3 square kilometers and a population of 140. Stone walls known as Ohte rise 3 to 4 meters in height along the edge of the village. These were originally built more than 150 years ago to protect island homes from winter storms, and they give the community a unique fortress-like appearance.

An observation deck on the island’s highest point offers a panoramic view of the Seto Inland Sea. Nearby is an extensive cavern, perhaps used by pirates long ago but now a popular tourist spot linked to the ogres’ den from Momotaro, a Japanese folktale about a hero born from a peach.

In the spring, thousands of cherry blossoms dye the island’s hills a delicate pink, while in summer, its beaches attract many swimmers and campers. Megijima also offers excellent recreational fishing. Every other year, the island hosts a grand shrine festival in which a large float bearing young drummers is carried into the sea in a demonstration of courage.



Ogijima, which lies just 1 kilometer north of Megijima, covers an area of 1.38 square kilometers and has a population of 160. Narrow lanes weave through the picturesque village that clings to the steep hillside. Lacking flat land suited for rice farming, the islanders raised cows instead and rented them out as plow animals to farmers on other islands in return for rice. This practice continued until the early 1950s.

Toyotamahime Shrine, which is visible halfway up the hill behind the port, is dedicated to a deity that ensures safe childbirth, and many expecting couples used to come here to pray. On the northern tip of the island stands an elegant lighthouse built of granite in 1895. Once used as the set of a popular movie, it has since been turned into a museum. Volunteers planted tens of thousands of Narcissus bulbs on nearby slopes, and these draw many visitors when they bloom in February.

Since the Setouchi Triennale began, a number of families have moved to the island. In 2014, the defunct elementary and junior high school was reopened, and the sound of children’s voices once again rings through the village. People have continued to relocate to Ogijima, starting up such enterprises as restaurants, a beauty salon and a library, and a new type of community is emerging through the collaboration of old timers and newcomers.



Shodoshima is the second largest island in the Seto Inland Sea, covering an area of a little over 153 square kilometers. Its population of over 26,000 is concentrated in the townships of Tonosho and Shodoshima. According to Japanese mythology, it was the tenth island of the Japanese archipelago to emerge from the sea.

Shodoshima’s soy sauce and somen noodle manufacturing industries date back over 400 years, while its tsukudani pickling and sesame oil industries which grew out of the former also have a long history. About 110 years ago, Shodoshima became the first place in Japan to successfully cultivate olives, leading to the establishment of many olive related industries.

The Shodoshima coastline offers striking views of the Seto Inland Sea, while the Inland Sea’s highest peak rises from the island’s center. Shodoshima offers an intriguing blend of nature and culture. Scenic sights include an elusive sandbar known as Angel Road and the spectacular Kankakei Gorge. The island has also retained many traditional customs and festivals, such as the Mushi-okuri Fire Festival and Noson (rural) Kabuki.



Oshima is located just 8 km from Takamatsu Port. It was once two tiny islands, but the channel between them gradually filled with sand, joining them together to make a single island of less than one square kilometer. During a historic battle between the Genji and Heike clans near Takamatsu in the 12th century, the corpses of defeated Heike warriors washed up on Oshima’s west shore where the islanders buried them. Pines grew up over their graves, and a grove of trees marks the spot to this day.

In 1909, the island became a sanitarium for people with Hansen’s disease (leprosy). Fear and prejudice led the Japanese government to adopt a policy of segregation, and victims of the disease were torn from their families and forced to live in isolated colonies like Oshima. The law stipulating forced quarantine was only repealed in 1996, with further legislation following in 2008. All residents of the Oshima sanitarium were cured many years ago, but the facility provides continued care and support for those who need it, as well as educational activities to raise public awareness of the disease and its tragic history.



Like neighboring Naoshima, this island is drawing attention for intriguing works by some of Japan’s foremost contemporary artists and architects, such as Kazuyo Sejima and Hiroshi Sambuichi. A quick 8-minute ferry ride from Hoden Port in Okayama, Inujima is a tiny island (area: 0.54 km2) with a population of just 50 people and can be explored entirely on foot.

In the past, the island’s high quality granite was quarried to build the castles of Edo, Osaka and Okayama. It continued to be sought after into the early 20th century. In 1909, a copper refinery was also established, and the island’s population swelled to 3,000 during the decade of peak production. When the refinery closed and the stone industry declined, however, the population dropped drastically. The art sites, however, are restoring life to the island as well as an appreciation for the beauty of this natural setting.



Shamijima was once located 4 km from the shore but in 1967, the channel was filled under a land reclamation project and Shamijima was an island no more. The history of human habitation is ancient, and pottery shards and stone implements found here date back to the Jomon period (12,000-300 BC).

There are also at least nine ancient burial mounds known as kofun on the hill at the island’s southern tip. The island appears by the name of Samine in a well-known waka poem penned by the famous poet Kakinomoto Hitomaro around 690 and contained in the Man’yoshu, Japan’s oldest poetry anthology.

In 1988, the graceful Seto Ohashi Bridge was completed, and Shamijima offers a striking view of this wonder of modern technology, the world’s longest two-tiered bridge. On the island’s west shore lies a sheltered beach that is highly popular in summer and a great place to watch the Inland Sea’s magnificent sunsets.



Situated in the Shiwaku archipelago, Honjima was once the political center of the Shiwaku Suigun, a maritime force that controlled the surrounding sea for several centuries. Tricky currents and hidden shoals make navigation in this region treacherous, and Japan’s land-based rulers relied on the expertise of local navigators and sailors for shipping and for naval protection. In the mid-nineteenth century, it was Shiwaku seamen who manned the Kanrinmaru, the first ship to carry Japanese across the Pacific to acquire the fruits of Western learning.

Honjima’s shipbuilders were also expert carpenters, a fact reflected in the village’s elegant traditional architecture. Many buildings date from the 18th and 19th centuries, and some are even older. In the Kasashima district, a whole neighborhood of such buildings has been skillfully restored. Kinbansho, the island’s former seat of government, has been converted into a museum housing such precious artifacts as documents stamped with the seals of Nobunaga Oda, Hideyoshi Toyotomi and Ieyasu Tokugawa, the three most influential leaders of the late 16th century.

A small island with a circumference of about 16 kilometers, Honjima today has a population of 330 people, the majority of whom are engaged in the fishing industry.



Takamijima lies to the west of Takamatsu city and can be reached from Tadotsu Port. Takamijima’s harbor and two small settlements are clustered around the island’s southern tip at the foot of a steep 300-meter hill. There is not much farmland, but for several centuries the island supported up to 1500 inhabitants who were engaged in shipping and fishing. More recently the pyrethrum plant, a natural insecticide, was cultivated for export.

The beautiful but slowly decaying houses that cling to the steep slopes and the sturdy stone terraces that support them serve as a poignant tribute to the building skills of the Shiwaku seamen. The unusual custom of dual graves (one grave for the body and another at which the family prays) is still practiced here.

The population has declined drastically in recent years, and cats now outnumber residents. Every year in September, however, people gather from neighboring communities to participate in a joint athletic meet that brings the quiet island to life.



Shaped like a ship’s propeller, Awashima was once three small islands linked by sandbars that gradually filled in. It covers a total land area of 3.67 square kilometers and has a population of 200. Located about 50 kilometers west of Takamatsu, it is a short 15-minute ferry ride from Suda Port in Takuma.

Awashima flourished from the 17th to 19th centuries as a port of call on the Kitamaebune shipping route, which ran from Osaka around the southern tip of Honshu and up the Japan Sea coast to the north. Japan’s oldest naval training school was established here in 1897 and produced many skilled sailors until it closed in 1987. The school building has since become part of the Awashima Ocean Memorial Park and serves as the island’s symbol. Time passes slowly here, providing visitors with a welcome refuge from a busy modern lifestyle.



Ibukijima is located about 60 kilometers west of Takamatsu and can be reached from Kanonji Port. The island rears up from the sea to form a rough tabletop of andesite and granite and covers an area of 1.05 square kilometers. As the coastline is mainly cliffs, the population of 400 is concentrated at the top. The slope extending up from the port is called shinzo-yaburi-zaka, meaning “heart-rending” hill, a name indicative of the steep climb.

The island’s prosperous fishing industry uses a combination of cast nets, small-scale trawl nets, and fixed shore nets to catch baby sardines. When processed and dried, these become Iriko, an essential ingredient in Japanese soup stock and cuisine. Ibuki Iriko, which is processed on the island immediately after being caught, is the most sought after brand in the country. Ibukijima is also the only place in Japan where people still use certain elements of the language spoken in 8th century Kyoto, making it a fascinating spot for linguists.



Situated roughly 500 km west of Tokyo, Takamatsu is the capital of Kagawa prefecture and the second largest city on the island of Shikoku with a population of 420,000 people. The city developed as a castle town from 1588 and had one of Japan’s three largest sea castles. Although the castle keep was dismantled in the 19th century, the original turrets remain as do some of the seawater moats, which are now extremely rare in Japan.

From the 16th to 19th centuries, Takamatsu developed into a major commercial and administrative center under the Tokugawa government. With the development of harbor facilities and a railroad in the late 19th century, Takamatsu Port became known as the gateway to the island of Shikoku. The port continues to serve as an important hub for both passenger and cargo ships between Shikoku and the many islands and ports on the Seto Inland Sea.


Uno Port

Uno Port is located on the southern tip of Okayama Prefecture in Tamano City, which stretches 44 kilometers east-west along a scenic coastline and has a population of 60,000. A moderate climate and sheltered inlets and bays makes Tamano an ideal port city, and its bustling harbor has prospered for centuries.

Shipbuilding, along with smelting and salt-making, underpinned city development, and Tamano’s townscapes still preserve many features of a typical shipbuilding town. Its farming and fishing industries continue to thrive, and local products include purple sweet potatoes, eggplants, pears, mandarin oranges, seaweed, and conger eel.

The train line between Okayama and Uno, as well as the ferry line between Uno and Takamatsu, were established in 1910. Uno was the final destination of the night train Seto from Tokyo and also served as a major terminus for ships joining Honshu and Shikoku. The port still bustles with people traveling to and from Takamatsu and the islands of Naoshima, Teshima and Shodoshima.


Exploring the Islands and Ports of Setouchi Triennale 2019


This weekly blog introduces the people, cultures and lifestyles of the different islands and ports that will serve as Setouchi Triennale 2019 venues. Please check out our Twitter, Instagram and Facebook as well.