What Is Otsushima Island? An Island Trip Combining Peace Education and Setouchi Nature
Otsushima Island (Ōzushima) is a remote island in the Seto Inland Sea reached by boat operated by the Otsushima Junkō ferry service from Tokuyama Port in Shunan City, Yamaguchi Prefecture, and it is known as the island where training for the "Kaiten" human torpedo was conducted.
It is a peace-education island where, beyond simply enjoying the sea views, you can quietly reflect on the memory of war and on peace while visiting the Kaiten Memorial Museum and the training base ruins.
From Tokuyama Port to Umashima Port it takes about 18 to 34 minutes by passenger boat depending on the order of port calls, or about 44 minutes by ferry, making it easy to visit even as a day trip and letting you touch both history and nature amid the calm air of the Seto Inland Sea.
Remote Island Access to Otsushima by Boat from Tokuyama Port
The gateway on the mainland side is Tokuyama Port in Shunan City, and to reach Otsushima you use the route operated by the Otsushima Junkō ferry service.
From Tokuyama Port to Umashima Port on Otsushima takes about 18 to 34 minutes by passenger boat, or about 44 minutes by the car ferry.
Because the island has several ports of call in addition to Umashima Port, it is reassuring to check the timetable and ports of call before boarding, according to the Kaiten Memorial Museum or the district you wish to explore.
From Umashima Port to the Kaiten Memorial Museum is about a 10-minute walk, and from the museum to the Kaiten Training Base Ruins is a further 10-minute walk, so the main spots are grouped within walking distance.
Because operating conditions can change due to weather or boat circumstances, check the service information from transport operators such as the Otsushima Junkō ferry service before departure.
The Nature of Otsushima Overlapping with Seto Inland Sea National Park
Part of Otsushima is designated as Seto Inland Sea National Park (Setonaikai National Park), and it retains scenery where you can feel the closeness of sea and mountains.
With the village roads, the harbor scenery, and the greenery of the slopes all close by, a way of spending your time that matches the island's air suits it better than rushing around the sights.
Because there are steep slopes and unpaved paths, wearing comfortable walking shoes and dressing for the season will make your walk more pleasant.
A Peace-Education Island That Confronts the History of Kaiten
On Otsushima, training for the "Kaiten" human torpedo was conducted in the final stages of World War II.
The Kaiten was a suicide weapon in which the pilot personally steered it to ram an enemy ship, and from September 1944 (Showa 19) this island was used as a training base.
Today there are facilities related to the Kaiten Memorial Museum and the training base, letting you learn about the war not as a distant event but as a memory embedded in places that remain on the island.
Highlights of the Kaiten Memorial Museum, the First Place to Visit on Otsushima
The centerpiece of a trip to Otsushima is the Shunan City Kaiten Memorial Museum, which exhibits materials related to the Kaiten.
Taking in the island's quiet atmosphere before entering the museum makes the meaning of the exhibits easier to grasp.
Reflecting Through the Belongings and Materials at the Kaiten Memorial Museum
At the Kaiten Memorial Museum, through belongings and materials related to the Kaiten, you can learn about the circumstances the young men of that time were placed in.
Letters and photographs the pilots addressed to their families are also on display, and it is a place best received as a time to face each word and object one by one.
The exhibits are arranged as a space for reading and reflecting quietly, not for consuming as sensational content.
Opening Hours, Admission Fee, and Closing Days of the Kaiten Memorial Museum
The Shunan City Kaiten Memorial Museum is located at 1960 Ozushima, Ozushima, and its opening hours are 8:30 a.m. to 4:30 p.m.
It is closed every Wednesday (or the following day if that is a public holiday) and during the New Year period (December 29 to January 3), and it may close temporarily during strong winds or dense fog.
The admission fee is 310 yen for adults, 250 yen per adult for groups of 30 or more, and free for students aged 18 and under and for infants.
Because the museum is on Otsushima, checking the boat route is just as essential as the opening information.
Checking the information from Shunan City and the museum will let you spend your time on the island with peace of mind.
Quietly Walking the Kaiten Training Base Ruins and Related Remains
Around the Kaiten Memorial Museum, remains related to the training have been preserved.
Rather than looking only at the buildings and structures, being conscious of their positional relationship to the sea and the routes of movement lets you understand the role the island played in a three-dimensional way.
Organizing how to view these places as part of peace education makes it easier to keep track of what you are seeing on-site.
| Place | Viewpoint | How to Engage |
|---|---|---|
| Museum | Materials and words | Read quietly |
| Base ruins | Relationship to the sea | Imagine the distance |
| Tunnel | Transport route | Watch your step |
| Lookout ruins | Role of observation | Read the scenery |
Gazing at the Sea at the Kaiten Training Base Ruins
The Kaiten Training Base Ruins are the site of a facility that was originally a test-firing range for the Type 93 oxygen torpedo, which from September 1944 (Showa 19) was used as a training base for the Kaiten.
Pilots were towed by a side-carrying boat (yokodakitei) to a buoy offshore of the base, and repeated steering training as realistic as actual combat along several training courses.
Standing before the remains that face the sea, the words you learned from the museum exhibits come to feel connected to the actual terrain and water surface.
Walking the Kaiten Transport Tunnel
The Kaiten transport tunnel is a passage about 250 meters long and about 4 meters high, dug to carry the Kaiten from the maintenance workshop to the training base by trolley.
Inside, traces remain where the rails were embedded in concrete, giving a glimpse of how transport was carried out at the time.
Because there are spots where the footing is dark and slippery, slowing your pace and letting your eyes adjust to the brightness as you view it will deepen your understanding.
Considering the Role of Observation from the Torpedo Lookout Ruins
The torpedo lookout ruins are the site established to observe and confirm, from near the summit of Mount Tategami (Tategami-yama), the performance of the Type 93 oxygen torpedoes test-fired from the island.
Given that a test-firing range for the Type 93 oxygen torpedo was located here, this lookout is thought to have been a place to verify the torpedoes' running and accuracy.
Gazing at the sea from a high vantage point makes it easier to imagine the background of how the island's terrain was used as a military facility.
Show Consideration for the Place of Remembrance When Photographing the Remains
When photographing the remains, you will want to avoid disrupting others' viewing and to stay mindful that this is a place of memorial and learning.
Where signs on-site indicate whether photography is permitted or the extent of accessible areas, please give priority to that guidance.
How to Enjoy an Otsushima Walk Savoring Nature and the Village
The appeal of Otsushima is not only the memory of war.
By slowly walking through the harbor, the village, and the plant scenery, you can also touch the present-day life of the island and the calm expression characteristic of Setouchi.
Because the way things appear changes with the seasons, it is easier to walk when you avoid narrowing your purpose too much and leave room to enjoy nature's changes.
| Season | How It Looks | How to Walk |
|---|---|---|
| Spring | Hint of flowers | Stroll from the port |
| Summer | Sea feels close | Beware of heat |
| Autumn | Scenery of the spikes | Check your footing |
| Winter | A quiet island | Mind cold protection |
The Bulrush Colony in the Omi District and Its Best Season
The Omi (Ōmi) district has a colony of gama (bulrush), a plant known for appearing in the old folktale "The White Rabbit of Inaba" (Inaba no Shiro Usagi).
It is said to grow densely on the site of former rice paddies reclaimed during the era of Mōri Domain rule.
Because bulrush puts out its brown spikes around early September, this period is the best season for seeing the colony at its most characteristic.
Since the appearance of plant scenery changes with the season and weather, rather than aiming only for photos, it is best to walk and accept the form the plants take in that season.
The Atmosphere of the Sekichūan Tea House and the Approach to Itsukushima Shrine
Deep within the bulrush colony stands the tea house Sekichūan, converted and repurposed from an old farm-tool shed.
The stone-paved approach path leading to the nearby Itsukushima Shrine winds among the bulrushes, making it an easy place to feel the island's quietness.
Because the approach path can be damp underfoot, please walk slowly while savoring the scenery woven by the waterside and the greenery.
Island Time Spent at Umashima Port and the Seaside
On Otsushima, the harbors and seaside scenery you pass on the way to your destination are also part of the trip.
Time spent waiting for a boat is not a gap in your schedule; it is island time for enjoying the sound of the waves and watching boats come and go.
Because the island has few large stores like those on the mainland, preparing drinks and light snacks around Tokuyama Port will let you spend your time at the harbor more calmly.
The Memory of Otsushima as an Island of Stone, Seen in the Leftover Stones from the Osaka Castle Reconstruction
Otsushima also retains a history different from the modern memory connected to the Kaiten.
The leftover stones from the Osaka Castle reconstruction serve as a clue that the stone around the island was connected to the history of the mainland.
Osaka Castle Stone Wall Material Remaining on Otsushima
During the Tokugawa clan's reconstruction of Osaka Castle, stones cut out for use as the castle's stone walls remain on the island.
The stone is said to be about 1 meter wide, about 2.5 meters long, and about 6 tons in weight, with the Mōri clan's ship mark carved into its surface.
The sight of such a large stone still remaining by the sea lets you reflect on the grandeur of Osaka Castle and the role Otsushima played in producing the stone material.
Viewing Otsushima from Perspectives Beyond the War Remains
When walking Otsushima, viewing it together with the memory of the stone, the harbor, the village, and the plants, rather than focusing too much only on the history of the Kaiten, broadens your impression of the island.
Thinking of multiple eras overlapping on a single island changes the density of what you learn even on a short walk.
Etiquette and Preparations for Otsushima to Know Before Visiting Japan
Otsushima is a sightseeing destination and at the same time a remote island where people live, including places of remembrance.
Prioritizing leeway over convenience and not packing your schedule for travel, meals, and sightseeing too tightly is the key to a pleasant stay.
| Situation | What to Do | What to Avoid |
|---|---|---|
| On the boat | Move quietly | Blocking the aisle |
| Memorial facilities | Check the guidance | Speaking loudly |
| Village | Give way on the road | Entering private land |
| Natural areas | Watch your footing | Picking plants |
Check the Otsushima Junkō Ferry Times
Because Otsushima is an island reached by boat, planning with the return boat in mind is important.
In particular, the museum closes at 4:30 p.m., so crossing over on a boat close to evening can leave you short on viewing time; boarding in the morning is recommended.
Check the timetable, fares, and operating conditions from the Otsushima Junkō ferry service or Shunan City's transport information, and act with extra leeway especially on days with unstable weather.
Value Quietness at Places of Remembrance
At the Kaiten Memorial Museum and related remains, before taking a photo you will want to consider what these places have been preserved to convey.
In the exhibition rooms and places connected to memorial services, lower the volume of your conversation and avoid disturbing other visitors' time.
Prepare Meals and Shopping with Plenty of Leeway
On a remote island, it is calmer to spend your time without expecting food and shopping in the same way as in front of a mainland station.
Prepare drinks, lunch, and any regular medications around Tokuyama Port before departure, and if you do use local shops or facilities, check their operating status in advance.
Summary: A Trip to Otsushima for Quiet Island Time and Reflecting on Peace
Otsushima is an island where, while walking through the nature of Setouchi, you can reflect on the history of the Kaiten and on peace.
At the Kaiten Memorial Museum and the training base ruins, rather than rushing to finish viewing the exhibits and remains, it is important to take time to absorb the weight of what is hard to put into words.
Touring the bulrush colony in the Ōmi district, the approach path leading to Itsukushima Shrine, and the leftover stones from the Osaka Castle reconstruction together, you can also see that the island's memory is not of a single era alone.
Before your visit, check the Otsushima Junkō route and the Kaiten Memorial Museum information, and on-site, remember your consideration for daily life and places of remembrance as you enjoy a quiet island trip.
