Exploring the Setouchi Region in 2023 - Home to Japan's Gorgeous Inland Sea Filled With Islands and Historical Marvels

Consisting of seven prefectures facing the Seto Inland Sea, the Setouchi Area hosts a wealth of incredible sightseeing spots, a calm sea, peaceful island scenery, historic townscapes, and renowned international art events such as the Setouchi Triennale. This article will outline the Setouchi region, giving you all the information you’ll need to plan the perfect Japan seaside getaway in 2023!

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Where Is Setouchi?

The Seto Inland Sea, located in the western area of the Japanese mainland of Honshu, is surrounded by the islands of Honshu, Shikoku, and Kyushu and is celebrated as Japan's largest inland sea. It spans approximately 450 km east to west and 55 km north to south, and boasts 7,230 km of shoreline and more than 700 islands. It has a temperate climate with a high rate of sunshine and low rainfall throughout the year, making it ideal as a tourist destination!

What Prefectures Are in Setouchi?

The Setouchi area consists of the seven prefectures of Hyogo, Okayama, Hiroshima, Yamaguchi, Tokushima, Kagawa, and Ehime, all of which face the Seto Inland Sea. Below is a profile of each prefecture:

Hyogo Prefecture

Hyogo Prefecture is a part of the Kansai region and has shorelines on the Sea of Japan to the north and the Seto Inland Sea to the south. With a total area of 8,401 km², it is the 12th largest prefecture in Japan. It boasts a wide range of localities, ranging from large cities to rural farming and mountain villages and outlying islands, making it a great destination for a variety of activities including ocean swimming, mountain skiing, and soaking in onsen (hot springs). With tourist attractions such as the World Heritage Site of Himeji Castle and Arima Onsen which is said to be Japan's oldest hot spring area, Hyogo Prefecture attracts many tourists from both Japan and abroad.

Hyogo Prefecture is also famous for its sake and is the number one producer of sake both in terms of production quantity and sales. In particular, the Nada Ward of Kobe City is considered to be Japan's foremost sake producing area and is home to many sake breweries that are famous nationwide. The prefecture is also known for its world-famous Kobe beef.

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Okayama Prefecture

Okayama Prefecture is a part of the Chugoku region of western Honshu. It is Japan's 17th largest prefecture with a total area of 7,114 km². Famous tourist destinations in Okayama include Okayama Korakuen, which is one of the Three Great Gardens of Japan; Kurashiki Bikan Historical Quarter, a beautiful townscape with white walled buildings along a canal lined with willows; and the Hiruzen Kogen Highlands, one of the most famous highland resorts in western Japan.

Okayama Prefecture is also celebrated for its thriving fruit farming industry owing to the temperate climate and limited rainfall, making it one of Japan's top producers of muscat grapes.

The Great Seto Bridge, which opened in 1988, is a 10 km bridge that connects Kojima in Kurashiki City, Okayama Prefecture with Sakaide City in Kagawa Prefecture. It is one of the world's longest bridges that can service both car traffic and trains. Visitors to the area can get fantastic views of 50+ islands in the Seto Inland Sea along with the Great Seto Bridge from the summit of Mt. Washu, known as Okayama Prefecture's foremost scenic spot.

Hiroshima Prefecture

Hiroshima Prefecture is located in the southern part of the Chugoku region. It has a unique, intricate shoreline on the Seto Inland Sea, with approximately 140 islands in the sea coming under the jurisdiction of Hiroshima Prefecture. It has a total area of 8,479 km²,  making it the 11th largest in the country.

The prefecture's capital, Hiroshima City, is a government ordinance city and the largest metropolis in both the Chugoku and Shikoku regions. Hiroshima has two World Heritage Sites, Itsukushima Shrine and the Genbaku Dome, and is a super popular tourist destination attracting hordes of visitors from across Japan and the world.

The Shimanami Kaido, which runs from Onomichi City in Hiroshima Prefecture and Imabari City in Ehime Prefecture, offers travelers wonderful views from the seven bridges connecting the Seto Inland Sea islands. It is also an extremely famous road for cycling!

Hiroshima is also Japan's number one producer of farmed oysters, accounting for more than half of those produced in Japan. Definitely be sure to try some oysters when visiting Hiroshima!

Yamaguchi Prefecture

Yamaguchi Prefecture is a part of the Chugoku region and has shorelines on the Sea of Japan to the north and Seto Inland Sea to the south. With a total area of 6,112 km², it is the 23rd largest prefecture in Japan. It has approximately 1,500 km of shoreline with vastly different but equally beautiful views on both of its coasts, with the Seto Inland Sea offering a gentle, calming ambiance with numerous islands and the Sea of Japan characterized by a rugged, dynamic shoreline.

The prefecture's tourist attractions include the Akiyoshidai Quasi-National Park, which has one of Japan's largest karst highlands along with the massive Akiyoshido Cave lying 100 m below ground, which is one of Japan’s largest limestone caves. Other highlights include Tsunoshima Bridge, which runs over a stunning emerald green sea, and the castle town of Hagi, famous for its elegant historical townscape.

Yamaguchi also hosts a thriving fishing industry, with Shimonoseki Port particularly renowned for its fugu (pufferfish).

Tokushima Prefecture

Tokushima Prefecture is in the eastern part of the Shikoku region and faces Wakayama Bay to the east and the Pacific Ocean to the southeast. It has a total area of 4,146 km², of which approximately 80% is mountainous. Its highest peak, Mt. Tsurugi, is 1,955 m high and is the second tallest mountain in Shikoku.

Tokushima is blessed with numerous destinations to enjoy its beautiful nature. This includes the Naruto Whirlpools in the Naruto Strait, which are among the largest tidal whirlpools in the world; Oboke and Koboke Gorges, which were formed by the Yoshino River over a period of approximately 200 million years; and the secluded Iya Valley, an untouched jungle retaining the visage of times past. Tokushima also brims with historic sites and traditional events, such as Ryozenji Temple, the first stop along the 88 temples of the Shikoku Pilgrimage, and the Awa Dance Festival, which boasts an extensive 400-year history.


Kagawa Prefecture

Kagawa Prefecture is in the northeastern part of Shikoku. With a total area of just 1,876 km², it is the smallest of Japan’s 47 prefectures and accounts for just 0.5% of the country's total area. It faces the Seto Inland Sea to the east, north, and west and is connected to Okayama Prefecture on the opposite shore of the Seto Inland Sea by the Great Seto Bridge - one of the world's longest bridges. The Sanuki Mountains, a mountain range running east to west, straddles the south of the prefecture and acts as a natural boundary with Tokushima Prefecture.

There are numerous historic sites and cultural properties in Kagawa, including Kotohira-gu, a shrine often lovingly called "Konpira-san of Sanuki"; Ritsurin Park, one of Japan’s largest and most famous gardens; and Marugame Castle, which is noted for its stone walls said to be the tallest in Japan. There are also plenty of natural wonders such as the "Angel Road," a path of sand that appears in the ocean during low tide.

Kagawa is also known for its thriving art scene, boasting dozens of spots to enjoy contemporary art. The Setouchi Triennale, a contemporary art festival held once every three years, is famous worldwide as an opportunity to enjoy the beautiful scenery of the Seto Inland Sea together with cutting-edge contemporary art. Naoshima, one of the sites of the Setouchi Triennale, is often referred to as the "art island."

Kagawa also calls itself the "udon prefecture" and is the number one producer of udon noodles in Japan and has the highest number of udon shops (per 10,000 residents).

Ehime Prefecture

Ehime Prefecture consists of the northwest quarter of Shikoku along with dozens of small islands in the Seto Inland Sea. With a total area of 5,676 km², it is the 26th largest prefecture in Japan.

It faces the Seto Inland Sea to the north and is connected with Hiroshima Prefecture on the opposite shore of the Seto Inland Sea by the Shimanami Kaido. It is known for its extensive natural beauty, which includes the Uwa Sea, famous for the stunning ria coastline; the Shikoku Karst, a magnificent highland area described as "Japan's Switzerland"; and Mt. Ishizuchi, the highest peak in western Japan nicknamed the "roof of Shikoku."

With numerous castles, such as Matsuyama Castle, Imabari Castle, and Ozu Castle, many of which are amongst the top 100 castles of Japan, Ehime Prefecture is the ultimate castle hopping destination! There are also loads of historic townscapes, such as Dogo Onsen, said to be the oldest onsen hot spring town in Japan; the castle town of Ozu; and Unomachi, which once flourished as a post town on the Uwajima Kaido highway.

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The Setouchi Climate - Paradise for Travelers with Warm Temperatures Throughout the Year!

The Setouchi area has a mild climate with a stable temperature throughout the year, making it easy to travel no matter the season.

Spring (March - May)

Spring is relatively warm and comfortable most days, however, there can be instability in the weather and thick fog around the Seto Inland Sea. Substantial temperature drops also occur with the mornings and evenings, so be sure to bring a light jacket or outer layer.

There are numerous famous cherry blossoms spots in the Setouchi region, such as Okayama Korakuen, one of the Three Great Gardens of Japan, and Ritsurin Garden, which was designated as a Special Place of Scenic Beauty by the government. If you are visiting in spring, definitely be sure to see the cherry blossoms in bloom! Spring is also the perfect time for outdoor strolls and a great time to enjoy the atmospheres of the castle town of Hagi and the Kurashiki Bikan Historical Quarter. There are also many spots to take in the cherry blossoms together with views of the Seto Inland Sea.

Summer (June - August)

Japan’s rainy season begins in June, which will naturally see substantially increased rainfall across the Setouchi region. Once the rainy season ends, temperatures will increase and lead into numerous balmy mid-summer days reaching 30℃ or higher. During this period, a phenomenon called "the evening calm of Seto" appears along the coast of the Seto Inland Sea, whereby the wind completely dies and the water becomes so still, it looks like a mirror. The weather is usually warm enough to be in short sleeves all day, but it may be handy to have something to wear on top.

If you are visiting the Setouchi area during the summer, be sure to fully take advantage of the beautiful sea! Some of the most popular ways to do this include driving or cycling on the Shimanami Kaido or visiting some of the outlying islands. Summer is also the perfect time to venture to the art island of Naoshima to enjoy a mashup of the beautiful sea and contemporary art.

Fall (September - November)

As the heat tends to linger through September, early autumn will still see many hot days. This is also peak typhoon season, so your travel may be affected by typhoons as late as October. While the weather tends to stabilize with continuing sun from October to November, temperatures will gradually decrease and there can be some frost on the mountains. Fall foliage will start to emerge in late October. Be sure to bring a jacket or light coat as it can get cold in the mornings and evenings.

The iconic Kankakei Gorge in the Setonaikai National Park is particularly famous for fall foliage. The ropeway that climbs up between the cliffs offers fantastic views of the spectacular gorge and the Seto Inland Sea.

Winter (December - February)

While winter is relatively warm along the Seto Inland Sea with little rainfall, there is enough snow in the mountains to enjoy skiing. Cold-weather clothing, such as sweaters and coats, will be required.

Relaxing in Dogo Onsen, one of Japan's three ancient hot spring areas, is highly recommended to warm up during the cold winter. This is also a good time to witness the sea of clouds from the "castle in the sky" of Bitchu Matsuyama Castle.


Average seasonal temperatures and rainfall in each prefecture are as below:

*Source: Japan Meteorological Agency (data on 1991-2020 averages)
Kobe CityOkayama CityHiroshima CityYamaguchi CityTokushima CityTakamatsu CityMatsuyama City

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Access From Tokyo or Osaka

The Setouchi area can be conveniently accessed from Tokyo or Osaka by air, shinkansen (bullet train), regular train, and long-distance bus, allowing you to choose the best method based on your arrival airport, final destination, price, and travel times.

The table below provides approximate travel times between the three international airports in Tokyo and Osaka and the major train stations and airports in each prefecture of the Setouchi region. Use it to help plan your trip!

(Note that the travel times are general estimates and actual flight and train schedules may differ.)

Baron von Richthofen, an esteemed German geographer who visited the Seto Inland Sea in 1860, was so taken by its beauty, he praised it as the most stunning place on earth. Visit the area yourself and marvel at each prefecture’s wonderous scenery that remains just as enchanting today!


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The information in this article is accurate at the time of publication.

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About the author

A Tokyo native who likes to read and visit art museums and is fascinated by the history and culture of other countries. After realizing the importance of learning from history, Okada is now going back to studying Japanese and world history.
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