Setouchi Adventure Tours: Enjoy Water Activities and Cycling on the Shimanami Kaido By Japan's Gorgeous Inland Sea

In this article, we introduce some adventure tours perfect to experience the beauty of the Setouchi area. "Setouchi" refers to the prefectures bordering the Seto Inland Sea, including Yamaguchi, Hiroshima, Okayama and Hyogo in the western Japanese mainland of Honshu, as well as Tokushima, Kagawa, and Ehime in northern Shikoku. Because all of them have access to the sea, they are popular destinations for marine sports. With one of these adventure tours not only can you enjoy the regions's vast nature and gorgeous sea but you can also learn more about is history and culture!

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"Setouchi" refers to the prefectures bordering the Seto Inland Sea, including Yamaguchi, Hiroshima, Okayama and Hyogo in the western Japanese mainland of Honshu, as well as Tokushima, Kagawa, and Ehime in northern Shikoku. Because all of them have access to the sea, they are popular destinations for marine sports. The Seto Inland Sea has numerous islands of varying sizes and is a center for kayaking and stand-up paddleboarding (SUP). The inland area of Shikoku boasts large rivers such as Yoshino and Shimanto, which offer great rafting and canoeing opportunities, as well as valleys perfect for stream climbing and canyoning. On the other side of the sea in southern Okayama, you’ll find a system of limestone caves that are fun to explore. In recent years, a cycling road connecting Hiroshima and Ehime has also become popular among cyclists who often ride it while enjoying amazing views and the relaxing sea breeze.

In this article, we’ll introduce the best places in Setouchi to experience the area’s stunning nature and all the fun outdoor activities to be had there.

■ SUP Around Suo-Oshima Island (Yamaguchi)

Suo-Oshima, located approximately 2 km off the western coast of Yamaguchi Prefecture, is the third largest of the roughly 3,000 islands dotting the Seto Inland Sea. It’s affectionately referred to as the "Hawaii of the Seto Inland Sea" because of its coastline, mountainous landscape, and warm climate. It originally got its nickname because of the laborers who moved to Hawaii for work during the Meiji Period (1868 – 1912) and brought back with them the culture and traditions of the islands.

The island features shops with tropical themes and people wearing aloha shirts. At the same time, a lot of rural areas around Suo-Oshima have remained unchanged for years, preserving the past in its most beautiful form, including scenes of streams flowing gently along rice paddies.

Stand-up paddleboarding, which originated in Hawaii, is a great way to enjoy this unique Japanese island that’s part tropical and part pastoral. With SUP, you’ll stand on a buoyant board and propel yourself across the water using a paddle while you enjoy the surrounding scenery as if you were taking a leisurely stroll on land.

This is a great way to relax and take in the clear blue sea, palm-lined beaches, and pastoral landscape of Suo-Oshima Island.

■ Sea Kayaking and SUP Around Miyajima (Hiroshima)

Miyajima is one of the most popular tourist destinations in Hiroshima, on par with the Atomic Bomb Dome. The island itself has been an object of nature worship since ancient times and today boasts primeval forests as well as a number of Shinto shrines and Buddhist temples.

The iconic Itsukushima Shrine is a designated World Heritage Site with grounds that extend into the sea. The shrine’s vermilion great torii gate off the shore of the island can be reached by foot at low tide, but takes on a mystic appearance when the tide is high and it appears to be floating on water.

If you want to see the gate up close when it’s towering above the surface of the sea, the best way to do so is by sea kayak or SUP. Both options give you a lot of freedom of movement, so once you've seen the great torii gate, you can paddle around the island and enjoy a tour of the wild beauty of Miyajima’s rugged coastline with cliffs that have been eroded by the ocean over centuries or take a break on a quiet beach. No matter how you like to spend your free time, Miyajima has an activity that’s perfect for you.

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■ Horse Trekking in Tamba-Sasayama (Hyogo)

The Tamba-Sasayama woodland, which has remained unchanged since ancient times, can be easily accessed from both Osaka and Kobe and is best enjoyed during a leisurely horse trekking tour.

Horse trekking in Tamba-Sasayama is more than just you sitting on a horse guided by someone else. You actually get to take the reins and control the horse, becoming one with your four-legged travel companion and enjoying the tour even more.

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■ Cycling on the Shimanami Kaido (Ehime)

Shimanami Kaido, an approximately 60-kilometer-long road from Onomichi City in Hiroshima to Imabari City in Ehime, connects numerous islands with bridges so that people can thoroughly enjoy the views of the Seto Inland Sea. It is also famous as the first cycling road in Japan built across straits.

In 2014, the Shimanami Kaido was selected as one of the "7 best bike routes in the world" by CNN Travel. It has since been attracting bike enthusiasts from around the world, living up to its reputation as the mecca for cyclists.

The cycling road goes through six islands and seven bridges with a constantly changing scenery that encourages cyclists to pedal harder so that they can get to the next amazing view. It is an exceptional experience to bike while enjoying the sight of the shimmering, blue sea and the feel of the ocean breeze on your face. There are also scenic beaches and “azumaya” gazebos selling local delicacies along the way, so even taking a break on the Shimanami Kaido makes for an unforgettable memory. With so many places to see, many people ride the route numerous times. You definitely want to take your time when traveling on this road.

■ Sea Kayaking in Tomonoura (Hiroshima)

Tomonoura in southeast Hiroshima Prefecture is a port town in the center of the Seto Inland Sea. It has flourished as "the port to wait for a favorable tide" since the Edo Period (1603 – 1867). There were many merchant houses and inns serving the crews of boats waiting for favorable sailing conditions, and the nightlights, shrines, and temples from those times can be found across Tomonoura to this day.

The best way to get a sense of Tomonoura as it was back then is to go sea kayaking and see the port from the same vantage point as the sailors. Sea kayaking is also a great way to take in the scenery of this port town and the torii gates on its shores. It is quite an experience to witness Abuto Kannon Temple, which juts out into the sea, from the sea. 

The nearby uninhabited Sensui Island is famous for its unspoiled nature and scenic beauty that, according to lore, enchanted even the godlike sennin sages. Sensui Island is also counted as one of the top 100 sunset-viewing spots in all of Japan. This is yet another spot that can be explored via sea kayaking.

Tomonoura has also been the setting for a popular Japanese animated film and a Hollywood movie. It’s a wonderful, beautiful place where the present and the past intertwine, and the best way to see it all is from inside a kayak.

■ Caving in Okayama (Okayama)

Okayama faces the Seto Inland Sea to the south and is home to the Great Seto Bridge, the world's longest railroad bridge, so it’s most often associated with the water. But its beauty also extends underground to the many caves found in the mountainous parts of the prefecture.

There's a lot of limestone in Okayama, so it makes sense that the prefecture boasts many limestone caves that have been created through erosion over millennia. As such, Okayama is one of the few places in all of Japan where you can enjoy limestone caving.

Caving trips are led by professional guides and always keep things interesting by going through narrow paths, waterfalls, natural pools of water, and more. Some paths even require a little underground stream climbing. There is a great feeling of satisfaction that comes from traversing the caves by foot.

At the end of your underground adventure, you will be treated to breathtaking views of countless stalactites and jellyfish-like limestone formations, with one awe-inspiring massive stalactite standing out among all of them. This mystic scenery that has been created over untold millennia is sure to captivate anyone lucky enough to see it.

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■ Sea Kayaking in the Seto Inland Sea (Kagawa)

The Seto Inland Sea is the largest inland sea in Japan with a whopping 3,000 islands of varying sizes gracing its waters. The beauty of this sea has been praised by many visitors from abroad, including the famous German physician and botanist Philipp Franz von Siebold. Today, it is recognized as part of the Setonaikai National Park for its scenic beauty.

The best way to enjoy the Seto Inland Sea is to take a sea kayaking tour through the islands. You can paddle from island to island, leisurely enjoying the beautiful scenery. The area is truly a kayaking paradise filled with caves, inlets, and other wonders that are in close paddling distance. Take an outdoor lunch on a deserted island with views of the dazzling blue sea and discover the underwater life by snorkeling! As the sun goes down, admire the new, mystic scenery that appears as the islands turn into silhouettes.

If you are considering joining a kayaking tour, be sure to check both the location and times.

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■ Paragliding in Matsuyama (Ehime)

There is also a way to see the islands on the Seto Inland Sea from up above in the sky. Harness yourself to parachutes and get lifted up high into the sky by the wind. Then enjoy the blue Seto Inland Sea and the blue sky together from high above!

There is no feeling quite like letting the wind take you on a leisurely walk in the sky. We recommend paragliding from Futami, a town near Matsuyama Airport, as it is easy to get to, the Seto Inland Sea is right in front of the town, and if the conditions are right, you can get fantastic views from 800 m above the ground. On a good day, you can see all the way to Honshu and possibly Suo-Oshima Island! You will also have a bird's eye view of the towns and the people living there, so you can get another perspective on the areas that you have visited. You will be paragliding in tandem with instructors, so the experience is open to people of all ages and fitness levels. Anyone can enjoy a trip in the sky!

■ Canyoning in Nametoko Gorge (Ehime)

Nametoko Gorge, a 12 km valley along a tributary to the Shimanto River which flows from western Kochi Prefecture, is designated as a national park and has huge, smooth granite rock surfaces that are very rare in Japan. If you are visiting Nametoko Gorge, take the opportunity to go canyoning, using these rock surfaces as slides to propel your body downstream.

There is a canyoning tour through which you can enjoy the thrilling experience of sliding down a 40 m portion of the 300-meter-long, 20-meter-wide Yukiwa-no-Taki Falls in one go. There are also natural waterways that are so narrow that only one person can pass at a time, so you will feel as if you are passing through a pipeline. There are infinite more ways to enjoy the area, such as jumping into a clear plunge basin and even climbing up the stream.

You can rely on a guide who has intimate knowledge of Nametoko Gorge to lead you through these fun activities. They will take the physical ability of participants into consideration, so it is a great and rather safe opportunity to enjoy playing in the river as if you were a child again. This is considered to be one of Japan's top canyoning centers, so be sure to see what it has to offer.

■ Rafting in Oboke/Koboke Gorges (Tokushima)

The Yoshino River, which flows from west to east in Tokushima Prefecture, has the largest drainage basin in Shikoku and has since ancient times been revered for bringing fertile soil to the basin downriver. There are beautiful views along it, such as in the Oboke and Koboke gorges, where water gushes between sheer cliffs, creating dramatic splashes as it hits rocks formed over time through erosion.

In the spring (April and May), the water level increases due to snowmelt and the river becomes one of Japan's fiercest rapids, giving it the nickname of "abaregawa" (a river that often overflows its banks). It is a famous spot for whitewater rafting, in which participants take an exciting ride down the river on a rubber raft. The feeling of going down the river as the boat turns around in the raging river, as if an airplane is in tailspin, is out of this world! It is the perfect activity to feel the power of the Yoshino River.

If you are not up for a wild ride or want to go with children, there are spots along the Yoshino River suited for a more gentle ride, so don't hesitate to give it a try!

■ Shower Climbing in the Yoshino River

Shikoku's iconic Yoshino River has many beautiful valleys, including the famous Oboke and Koboke Gorges mentioned above for whitewater rafting. One interesting valley is Iya, where the iconic rivers of Iya and Matsuo flow. It is a deep valley that is approximately 10 km long. The water flowing through it is so clean and clear that you can actually drink it, which is why it gained a reputation as a secluded region that retains its pristine beauty.

"Shower climbing" is highly recommended if you want to play in the waters of the beautiful Iya Valley. In a shower climbing tour, you will climb up rock surfaces that have water flowing down them and walk in the stream while enjoying the surrounding greenery. There are also opportunities to jump into plunge basins and slide down small waterfalls. It's a great opportunity to relax while getting your body moving! Some spots may be difficult to traverse through, but there's a sense of achievement when you do. You'll also have the full support of expert tour guides, so why not consider experiencing this secluded part of Japan?


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Shikoku Feature

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

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