[The Shimanto River and the Niyodo River] What and where are the best parts? Explanations of attractions such as submersible bridges, places to see Niyodo blue, and how to enjoy these rivers, all in one place!

The Shimanto River is known as “Japan’s last remaining clear stream,” while the Niyodo River is known as the “miraculous clear stream.” A visit to each of these limpid rivers is a once-in-a-lifetime experience, but what is the difference between them, and what are their features?
This article offers an easy-to-understand explanation about each river’s attractions and how to enjoy them. It answers questions such as: Where can you see Kochi’s quintessential submersible bridges (chinkabashi), and the mysterious Niyodo Blue? When is the best season to visit? Find out all sorts of information, about the hidden gems of the area to enjoy with hot springs, gourmet dishes, and activities!

What is the Shimanto River? What are its best features?

The Shimanto River is a class A river that flows 196 km through the western part of Kochi Prefecture. Its source can be found on Mt. Irazu in Tsuno Town, Takaoka District, located on the prefectural boundary with Ehime Prefecture, and it runs into the Pacific Ocean after passing through numerous cities and towns, including Shimanto City and Shimanto Town.
The Shimanto River’s greatest feature is its abundance of nature. Its essential natural form has been preserved from its upper reaches to its lower reaches, so it retains the scenery of Japan’s original landscapes. Many bridges that are submersed when the river rises (chinkabashi) cross its waters, and these also form scenery that has come to symbolize the Shimanto River.

Why is the Shimanto River called the “last remaining clear stream”?

No major (man-made) dams have been built across the main current of the Shimanto River, known as the “last remaining clear stream.” This means that its vast natural world has been preserved, untouched.

Its abundant currents nurture diverse biological systems, supporting many living creatures such as ayu fish and freshwater shrimp.

Representative traditional fishing methods such as hiburi (fire) fishing and shibazuke (wooden trap) fishing have been carefully passed down, and a rich culture formed from the close coexistence between the people and the river is very much alive.

The best season to visit the Shimanto River is...?! Recommended times and highlights

The natural world of the Shimanto River basin experiences four seasons, and the way of life of the people who live with the river is still vividly preserved to this day. Here, you can enjoy different charms in each season.

In spring, the river is surrounded by new greenery—the blooming field mustard and cherry blossoms create a wonderful contrast between the submersible bridges and the flowers. This is the best season for walks and cycling. In summer, the river is at its busiest thanks to the popularity of activities on its waters, including canoeing, SUPs, rafting, and yakatabune pleasure boats.
You can enjoy driving and taking photos along the river’s middle course and upper reaches in the fall, when the leaves turn crimson—the tranquil scenery will sooth your heart. Winter sees an expanse of fantastical landscape wrapped in morning mists and clouds, and the small number of tourists means you can savor the river’s peaceful countenance at your leisure. A visit to multiple hot springs in Oku Shimanto Hot Spring Town is a pleasure unique to this season.

Recommended gourmet cuisine offering a taste of the seasons

In summer, the river welcomes the season for natural wild ayu fish, eels, and freshwater shrimp.

Savor these salt-grilled or as tempura in local eateries or on a yakatabune pleasure boat.

Fall is the time for chestnuts and the fragrant citrus fruit “bushukan,” which enhances the taste of dishes with its refreshing acidity. Enjoy seasonal delights nurtured in Shimanto’s seasons!

[Upper reaches] Highlights of the Shimanto River (1)

The mysterious river source and Yusuhara, the town above the clouds

The Shimanto River headwaters begin in Mt. Irazu in Tsuno Town, close to the border with Ehime Prefecture.
The limpid water gushing from deep in the forest eventually becomes a great river; here, where it all starts, you’ll find untouched nature and an atmosphere of wonder and mystery.
Yusuhara Town, which is similarly located near the river’s upper reaches, boasts stunning buildings designed by architect Kengo Kuma that make the most of wood and light, including the Kumo no Ue no Library (Yusuhara Town Library) and Kumo-no-Ue-no-Hotel. This is a must-see spot, even if you're not into architecture. You can also enjoy a highland drive, views of starry skies, and a trip around an area with a sea of clouds.

[Middle course] Highlights of the Shimanto River (2)

Vistas created by submersible bridges, river fun & gourmet experiences

You’ll find large numbers of submersible bridges, known as chinkabashi, over the middle course of the river. These structures are typical of the Shimanto River.
Iwama Chinkabashi and Misato Chinkabashi are especially popular and make ideal spots for photos. The fantastical form of the bridges suspended in the morning mist and the landscape created when the sunset dyes the river surface deep red are exceptional sights.
This area offers a whole range of activities such as canoeing and SUP, allowing you to experience the Shimanto River’s magnificent waters for yourself.
Another appeal of the middle course is its natural wild eels. Eels caught using traditional fishing methods are ever-popular as a local delicacy for their high quality fat and a firmness unique to individuals nurtured in the river.

[Lower reaches] Highlights of the Shimanto River (3)

Gentle riversides and the natural world of the Shimanto River as it continues on to the sea

In its lower reaches, close to Shimanto City, the river widens further, and its flow becomes even calmer.
Join one of the yakatabune pleasure boat cruises that float gently on these waters to enjoy the relaxed landscapes with grassland at the river’s edge, mountains, and seasonal wild birds from the river.
You can also make the most of activities on the water such as windsurfing that takes advantage of the breezes. On top of this, the Shimanto River runs into Tosa Bay where you can have fun whale watching from spring to fall—you could encounter whales and dolphins such as Bryde's whales, common dolphins, and Risso's dolphins.
Experience the expanse of the Shimanto River and the richness of its natural world in this area where the river meets the sea.

Experience authentic rafting on the Yoshino River in Tokushima!

Don’t forget the Yoshino River that runs through Kochi Prefecture and Tokushima Prefecture as you dynamically enjoy Shikoku’s natural world! The Yoshino River is well known as a spot with some of Japan’s best rapids, and you can ride its swift currents and large waves in an authentic downriver experience. Guided tours are also available, giving peace of mind to beginners. This beautiful landscape formed of valleys weaving between mountains allows you to make the most of both adventure and a dynamic natural world that is different to the serenity of the Shimanto river.
(Oboke Iya Tourist Navigation)https://miyoshi-tourism.jp/rafting/
(Tosa-Reihoku Tourism Association)https://tosareihoku-kanko.com/play/#kawa

The Yoshino River basin is also an area with a unique and long-flourishing culture of indigo dyeing. We recommend experiencing Tokushima’s distinctive history and culture for yourself.
If you want to learn more about the magnificent land and stunning scenic spots in each area of Shikoku, check out our feature on geoparks.

See "Shikoku’s Geoparks: A Complete Guide"

Head out to visit the chinkabashi, submersible bridges over the Shimanto River!

Takahi Chinkabashi [left]
This submersible bridge crosses the uppermost reaches of the Shimanto River's main current, and is also known as Omata no Chinkabashi. Located 18 km downstream of the Shimanto River headwaters, this is a special place where you can feel the start of its clear stream."

Kumaaki Chinkabashi [center]
The second submersible bridge over the main current of the river, known as a famous spot for ayu fishing. Kumaaki Spring, one of Tosa’s 40 famous waters, can be found nearby. New greenery, clear flowing waters, and spring water come together to form a bountiful spot where you can make the most of many of nature’s blessings at once."

Nagano Chinkabashi [right]
This everyday crossing connects Makinono Village and Nagano Village. It is located close to Tenmangumae Camping Ground, enabling you to enjoy outdoor activities by the upper reaches of the Shimanto River.
 
Ittohyo Chinkabashi [left]
This is the oldest existing submersible bridge, built in 1935, and a registered national tangible cultural property. It is characterized by its idiosyncratic construction method of having no central pier. It is not currently possible to cross this bridge, but it is still well-known as a spot for painted log carp floats in the season for new greenery, and for summer fun in the water.

Shimizu Chinkabashi (Shimizu Ohashi Bridge) [center]
This is the longest submersible bridge over the river’s upper reaches. It stands high above the river surface and is rarely submerged. It is well-loved by anglers as a good spot for ayu decoy fishing.

Wakai Chinkabashi [right]
This bridge was temporarily destroyed by a flood but was rebuilt in 2019. The completion of Wakai Ohashi bridge means it is no longer used as an everyday crossing, but it stands as a historically significant bridge that tells the story of nature’s power in the Shimanto River.

 
Mukaihirose Chinkabashi [left]
A submersible bridge located in the center of stunning scenery, downstream of Iejigawa Dam in an s-shaped meander.

Jogu Chinkabashi [center]
This bridge connects Taishokitanokawa Village and Jogu Village. It has a unique form with many piers, and holds high cultural value as a submersible bridge representative of the village-dotted landscape along the middle course of the Shimanto River.

Kamioka Chinkabashi (Mukaiyama Bridge) [right]
Officially named Mukaiyama Bridge, this structure is popular for its pretty curved lines. Its proximity to National Route 381 makes it easy to access. Its elegant shape was designed based on Kuchiyanai Chinkabashi.
 
Satokawa Chinkabashi [left]
This bridge’s piers washed away multiple times due to flooding, creating its unusual form with a missing pier in the center. *Part of the bridge is currently collapsed and there are no prospects of restoration.

Kayabukute Chinkabashi (Shintani Bridge) [center]
This submersible bridge became famous when it was used on one of JR’s full moon posters, and it is also well-known as a sightseeing spot visited by Yuzo Kayama and his wife for filming. The current is gentle here and there is also a river beach, making it a fun spot for summer camping.

Daiichi Mishima Chinkabashi [right]
An unusual bridge that crosses to the Shimanto River’s largest island, Mishima. It is also popular among railway fans as the JR Yodo line runs parallel to the bridge.
 
Daini Mishima Chinkabashi [left]
This bridge connects Mishima and Todoroki Village. It is an important everyday crossing that connects the island with the mainland; visit it as a set with Daiichi Mishima Chinkabashi.

Hage Chinkabashi [center]
This is an important access point for Hage Village, and, as a valuable bridge that supports the everyday life and culture of the Shimanto River lower reaches, it tells us about local history and culture.

Nakahage Chinkabashi [right]
This is an important everyday crossing over the river’s lower reaches, and continues to function as a bridge essential for the daily lives of local people. It supports the local community amidst the rich natural environment of the Shimanto River.
Nagaoi Chinkabashi [left]
Even today, this structure plays a key role as a bridge closely linked to everyday local life. It creates a wonderful vista in harmony with the natural world of the Shimanto River.

Iwama Chinkabashi [center]
This is one of the quintessential submersible bridges over the Shimanto River. It is well-loved as a sightseeing spot in Nishitosa Village, as well as a popular location for playing and diving in the river. It bustles with many tourists in the summer.

Kuchiyanai Chinkabashi [right]
This bridge’s official name is Yanai Ohashi Bridge, and it is an important structure that was used as a reference when other submersible bridges were built. The design of Kamioka Chinkabashi (Mukaiyama Bridge) in particular was created using this bridge as a model.
Katsuma Chinkabashi [left]
This submersible bridge is popular among tourists—it is a scenic spot visited by many keen photographers, set against the backdrop of the majestic flow of the Shimanto River and its stunning natural environment. It is also a popular point for downriver tours.

Takase Chinkabashi [center]
This important bridge connects Tadenokawa with Takase, crossing over a wide part of the river. The bridge offers fantastic views, and is an exemplary spot to experience the magnificence of the Shimanto River.

Misato Chinkabashi (Fukaki Chinkabashi) [right]
Officially known as Misato Bridge, this structure boasts particularly lovely scenes of the Shimanto River lower’s reaches, and a calmer atmosphere than Sada Chinkabashi.
   
Sada Chinkabashi (Imanari Bridge)
This is the longest submersible bridge over the Shimanto River’s lowest reaches, and became famous overnight as a location used in the drama “Late Blooming Sunflower (Osozaki no Himawari).” It is the bridge closest to the mouth of the river, and is representative of Shimanto River tourism.

 

Bonus: Shikoku’s characteristic architecture

Similar to the submersible bridges over the Shimanto River, buildings rooted in local communities are dotted around each area of Shikoku. You’ll find architecture of all genres and periods, including traditional townscapes and castles, modern art museums and public facilities with a high level of design, and buildings in harmony with nature.

Why not add an architectural perspective to your trip to Shikoku?

See feature about Shikoku’s famous buildings and historic architecture

Recommended accommodation area for a Shimanto River journey: Oku Shimanto Hot Spring Town

Oku Shimanto Hot Spring Town is spread over the area of the upper reaches of the Shimanto River, and includes five quiet hot spring inns surrounded by mountains.
Among these, the popular Goroku Onsen, located in the area of the source of the Shimanto River, offers the charms of an outdoor bath with free-flowing water directly from the hot spring and wonderful valley views as well as an indoor wood-scented bath, comfortably soothing the tiredness of your trip.
Why not refresh your mind and body by soaking in a hot spring in the clear air of a quiet mountain site, and savoring regional dishes made using salt-grilled river fish and local vegetables?

What is the Niyodo River? What are its best features?

The Niyodo River is a class A river, 124 km long, that flows through Kochi Prefecture and Ehime Prefecture. Its source lies on Mt. Ishizuchi in central Shikoku, and it flows toward the southeast, running into Tosa Bay.
The greatest appeal of the Niyodo River is its characteristic “Niyodo blue,” a mysterious azure color that has become synonymous with the river. This clear blue color that draws you in is a result of the reflection of light, the geological features of the riverbed, and the outstanding water quality, and never fails to mesmerize visitors.

The river has been selected multiple times as one of the “rivers with the best water quality” by the Ministry of Land, Infrastructure, Transport and Tourism, and you can enjoy activities such as canoeing, SUP, and valley trekking on and around its waters. Other highlights include the waterfalls, valleys, and submersible bridges dotted around the river basin. Its untouched natural world and mountain village scenery, where the tea fields and rice fields of Japan’s original landscapes remain, are also part of its charm.

Why do people boast about the good water quality and its mysterious “blueness”?



The extraordinary clarity of the water is the reason for the beautiful azure color known as Niyodo blue. There are very few impurities in the water, so it strongly reflects only the short-wave blue light in the sunlight, and our eyes see it as blue.

The high level of transparency has come about for several reasons: the water flows rapidly through the precipitous topography, making it difficult for impurities to accumulate; the water temperature is low, preventing the algae that impede transparency from multiplying; and the hard bedrock, a geological feature, means that earth, sand, and mud that cause cloudiness don’t really materialize. On top of this, the riverbed is made up of a blue-green stone called greenschist, which further enhances the azure color. All these conditions come together to create the color of the clear waters of the Niyodo River.

The best season to visit the Niyodo River is...?! Recommended times and highlights

The appeal of the Niyodo River lies in its diverse natural visage that changes with the four seasons.

In spring, cherry blossoms and field mustard bloom by Asoo Chinkabashi and in Miyanomae Park, while the dazzling new greenery of Nakatsu Gorge and Yasui Gorge gives the river’s surface a refreshing hue. In summer, the water levels are stable, making this the season to see Niyodo blue at its glittering best. The clear azure water surface gleams even more brightly around noon, when the sun is directly overhead.

Fall is the season to enjoy the wonderful contrast created by the fiery red leaves and Niyodo blue in Nakatsu Gorge and Yasui Gorge, while winter is engulfed in quietness, with few tourists. The river becomes all the clearer in this season, and you can make the most of winter’s uniquely dignified natural beauty, including fantastical scenery suspended in the morning mists and the icicles that glitter in the mountains.

We also recommend activities for each season


You can enjoy various activities in each season in the Niyodo River area.

In spring, it is popular to hike through Nakatsu Gorge and Yasui Gorge, surrounded by new greenery.
Summer, when the water levels are stable, is the best time for SUP, canoes, and playing in the river.

A little further downriver you’ll find a calm area, close to the three major places to see Niyodo blue, where you can really get yourself moving in this vast natural world and experience the clear steams with your whole body.

[Yasui Gorge] Where can you see Niyodo blue? (1)

The deepest, most mysterious blue

Yasui Gorge is a quintessential spot for Niyodo blue. A tributary of the Niyodo River, the Yasui River, flows through this valley, and here you’ll find the particularly popular Suishobuchi pool with striking deep blue waters so clear you can see the riverbed. Sunny days only enhance its beauty.
The valley is also dotted with several scenic spots, including the Hiryu Falls and a check dam, and you can enjoy the wonderful landscapes from the walkways and bridges. It offers an expanse of stunning scenery during the seasons for new greenery and crimson leaves, mesmerizing the people who visit.

[Nikobuchi] Where can you see Niyodo blue? (2)

The water falling into the waterfall basin gleams a brilliant blue in this representative Niyodo blue spot. It is said that this truly is Niyodo blue. This small, deep pool is surrounded by forest, and takes on different appearances as the incoming light changes with the weather and time of day.
For the sake of nature conservation, entry into the pool is currently limited, but you can admire it from a designated viewing deck. This can be reached by walking for a few minutes along a paved path and up some stairs from the carpark, making it comparatively easy to visit. When you enjoy the wonderful scenery, make sure you follow the set rules and take care to consider the natural environment.

[Nakatsu Gorge] Where can you see Niyodo blue? (3)

Omogo Gorge extends across the southern foot of Mt. Ishizuchi in Ehime Prefecture, the source area of the Niyodo River. Its clear waters and the beauty of its valley make it popular spot!
It offers superlative landscapes of emerald-green waters and massive granite rock faces, and is known as the gateway to climb Mt. Ishizuchi—it is also perfect for walks among nature and viewing crimson fall leaves.

Have a look at our special feature on geoparks too for a trip that will take you around Shikoku’s magnificent topography.

Ehime’s valleys, Mt. Ishizuchi, and Omogo Gorge are also full of highlights!

Omogo Gorge extends across the southern foot of Mt. Ishizuchi in Ehime Prefecture, the source area of the Niyodo River. Its clear waters and the beauty of its valley make it popular spot!

It offers superlative landscapes of emerald-green waters and massive granite rock faces, and is known as the gateway to climb Mt. Ishizuchi—it is also perfect for walks among nature and viewing crimson fall leaves.

Have a look at our special feature on geoparks too for a trip that will take you around Shikoku’s magnificent topography.

Head out to visit the chinkabashi, submersible bridges over the Niyodo River!

Omori Chinkabashi [left]
This submersible bridge crosses the upper reaches of the Niyodo River in the Mori area of Niyodogawa Town. Its girder and piers are thinner than those of other submersible bridges, and it is characterized by its delicate beauty. It is especially pretty in the cherry blossom season. Oodo Dam is located nearby.

Kuki Chinkabashi [center]
This is Kochi Prefecture’s oldest submersible bridge made of reinforced concrete. It is located in the Kuki area of Niyodogawa Town, and its beautiful arched form stands among rough rocks in harmony with the natural world. There is a striking contrast between the Niyodo blue and the rocks.

Nakaniyodo Bridge [right]
This submersible bridge stands in the Ochi Tei and Ochi Ko areas of Ochi Town and connects the central part of Ochi Town with the Imanari area. Unusually for a submersible bridge, this is a structure with separate parts for walking and vehicles. It offers beautiful scenery with Mt. Yokogura serving as a backdrop, and combining a visit here with a trip to view the cosmos in nearby Miyanomae Park is a popular choice.
 
Asoo Chinkabashi [left]
Located in the Kamaida area of Ochi Town, this bridge is well-known as a setting of the film “Belle (The Dragon and the Freckled Princess).” It is a popular pilgrimage spot and boasts great views set against the townscape of Kamaida village; the vista from Asoo Chinkabashi observation point is also a must-see.

Kataoka Chinkabashi [center]
This submersible bridge is located in Kataoka in Ochi Town, and connects the Kataoka area with the Minami-kataoka area. It is a popular subject for photos taken at an angle that includes the streetscapes of the Kataoka area in the background, and offers a landscape where nature and villages are in harmony.

Nagoya Chinkabashi [right]
This submersible bridge is the longest (191 meters) that crosses over the Niyodo River, stretching over its lowest reaches, and is located in the Nagoya area of Hidaka Village. It is an important everyday crossing that connects Hidaka Village and Ino Town, with four passing places. The water here is shallow, and swimming fish are visible in its Niyodo blue, making this one of the best spots to experience Niyodo blue’s beauty.

Tosa washi paper, a traditional craft made in the Niyodo River basin

The Niyodo River basin has abundant clear water, and Japanese paper-making flourished here, taking advantage of this blessed resource. In particular, Ino Town is the central production area for Tosa washi (Tosa traditional Japanese paper), one of Japan’s three major types of washi paper with a history of over 1,000 years. Even now, craftspeople carefully create each sheet by hand, from processing the raw materials of paper mulberry and paperbush to the final handmade paper product.

Tosa washi is characterized by being so thin it is almost transparent, flexible, and strong. It is used in a wide range of fields—as shoji paper (for traditional wood-and-paper doors, etc.) and calligraphy paper, and in recent years, in interiors, lighting, and art pieces, too. The town has facilities offering handmade paper experiences and workshop tours, so why not get involved and create a memory of your trip?

Recommended accommodation area for Niyodo River sightseeing: Kumakogen Town

Kumakogen Town in Ehime Prefecture is located close to the Niyodo River basin. This highland town with a rich natural world is spread across Shikoku’s mountains. It is cool even in the summer, and full of clean air—a perfect area for people who want to enjoy a quiet stay. It offers various styles of accommodation, including pensions, inns among the mountains, and camping grounds, and at night the star-filled sky seems within your reach.

Travel a little further, and the magnificent scenery of Shikoku Karst Natural Park, one of Japan’s three great karsts, awaits you. Here, you can hike among wonderful vistas made up of grasslands and white limestone stretching as far as the eye can see on a highland 1,400 meters high.
Take leisurely strolls, and feast on rich local cuisine. Enjoy a carefree trip through the natural world. This is the perfect place if you want to travel in this way.

I want to travel around in a car. Introducing a model course!

Public transport is limited in the area around the Shimanto River and the Niyodo River, so we recommend accessing it in a car.

Make the most of local gourmet food and sightseeing spots in the area as you drive along the mountain roads of Shikoku and enjoy its spectacular scenery!

 

[The Shimanto River and the Niyodo River] Each river is amazing in its own way!

Which is better, the Shimanto River or the Niyodo River? The answer: they’re both amazing! Enjoy the slow and majestic flow of the Shimanto River, or the beautiful and breathtaking blue that is one of the appeals of the Niyodo River. Each river offers an abundance of unique landscapes and experiences. Try visiting once and you’ll find yourself wanting to go back again and again to different places in different seasons—why not start your trip along the clear, charm-filled currents with a spot that takes your fancy?

One essential element of your journey are the gourmet dishes unique to the local area. The feature article below introduces the specialty products and foods of each area of Shikoku, including Kochi’s own specialty, exquisite katsuo-no-tataki (seared bonito). Why not set off on your next trip with Shikoku’s food as your theme?