Somewhere between Hiroshima and Shikoku, a ribbon of road lifts itself off the earth and threads through six islands scattered across the Seto Inland Sea. This is the Shimanami Kaido — a 60-kilometer cycling route that connects Onomichi in Hiroshima Prefecture to Imabari in Ehime Prefecture, crossing some of the most visually arresting bridges in Japan. It is not an exaggeration to say that this is one of the finest cycling experiences anywhere in the world, and September, when the brutal summer heat finally loosens its grip and the light turns golden over the water, is arguably the best month to ride it.
The route is not a single highway but a patchwork: dedicated cycling paths that spiral up and over six massive suspension and cable-stayed bridges, connecting island roads that wind through fishing villages, citrus groves, and hillside shrines. You ride at your own pace, stop where curiosity pulls you, and for most of the journey the Seto Inland Sea stretches out on both sides — impossibly blue, studded with islands, dotted with fishing boats. It is the rare cycling route where the infrastructure itself is half the spectacle.
Planning Your Ride: One Day or Two?
The most common question is whether to do the Shimanami Kaido in one day or two. The answer depends on your fitness and what you want from the experience. The full route is about 60-70 kilometers depending on detours, with roughly 500 meters of cumulative elevation gain (the bridge approaches are long, gradual spirals, not steep climbs). A fit cyclist can complete it in 4-5 hours of riding time. But rushing the Shimanami Kaido defeats its purpose — half the joy is in the stopping.
For most visitors, a two-day ride with an overnight on one of the islands is the ideal approach. Ikuchijima (with the temple town of Setoda) and Omishima (with its museums and beaches) are the most popular overnight spots. This pace lets you explore side roads, swim at quiet beaches, eat at local restaurants, and watch the sunset paint the bridges gold.
If you only have one day, start early from Onomichi (the 7:00 AM ferry to Mukaishima gets you ahead of the crowds) and plan to arrive in Imabari by late afternoon. Skip the deeper island explorations and focus on the bridges and the main route.
Bridge by Bridge: What to Expect
Each of the six bridges has its own character, and the cycling approach to each is part of the experience — long looping ramps that climb gradually, giving you expanding views of the sea below.
Innoshima Bridge — The first crossing after the short ferry from Onomichi to Mukaishima sets the tone. You ride underneath the bridge deck on a separate cycling path, with the sea directly below through the grating. It feels like flying. On the far side, the small island of Innoshima has a charming old town with a sumo museum (sumo has deep roots here) and views from Shirataki Mountain.
Ikuchi Bridge — The longest cable-stayed bridge on the route arcs gracefully over the channel. The approach ramp spirals upward through citrus orchards, and at the top the view opens across the water to a chain of islands fading into the haze.
Tatara Bridge — Many riders consider this the highlight. At 1,480 meters, it is one of the longest cable-stayed bridges in the world, and the cycling path runs along the outer edge with nothing between you and the panorama below. There is a famous acoustic point at the base of the tower where you can clap and hear the sound ring upward through the cables.
Omishima Bridge — A compact, pretty bridge that delivers you to Omishima, the largest island on the route and the one most worth lingering on. The Oyamazumi Shrine here is one of Japan's most important Shinto sites, housing an extraordinary collection of samurai armor and weapons — more designated national treasures than any other shrine in the country.
Hakata-Oshima Bridge — Two bridges connected by a small island, creating one continuous crossing. The view from the midpoint, with bridges stretching in both directions and the sea below, is a popular photo spot.
Kurushima-Kaikyo Bridges — The finale. Three consecutive suspension bridges spanning the Kurushima Strait, totaling over 4 kilometers. This is the longest series of suspension bridges in the world. The current here is powerful — you can see it swirling below — and ships pass through constantly. You arrive in Imabari feeling like you have crossed an ocean.
Island Detours Worth Taking
The main route is spectacular, but the islands between the bridges reward curiosity.
On Ikuchijima, the town of Setoda is a small treasure. Kosanji Temple is a private temple built by a wealthy businessman in honor of his mother — an exuberant, sometimes eccentric complex that includes reproductions of famous Japanese architectural landmarks and a dazzling marble sculpture garden called the Hill of Hope, designed by the sculptor Kazuto Kuetani. The views from the marble terrace across the rooftops and harbor are worth the side trip alone. The nearby Hirayama Ikuo Museum of Art houses works by one of Japan's most important modern painters, who was born in Setoda.
On Omishima, beyond the Oyamazumi Shrine, the Tokoro Museum and Toyo Ito Museum of Architecture showcase contemporary art and design in beautiful natural settings. The island's quiet beaches — particularly Morikuni Beach — are perfect for a swimming break in September, when the water is still warm but the beaches are almost empty.
Bicycle Rental: How It Works
The Shimanami Kaido has an exceptionally well-organized rental system. The main operator is the Shimanami Japan bike rental network, with terminals at both ends (Onomichi and Imabari/Sunrise Itoyama) and on each island along the route. You can pick up a bike at one end and drop it off at the other — the one-way drop-off convenience is what makes the route so accessible to visitors.
Rental costs are remarkably affordable: around 3,000 yen per day for a standard cross bike, with a 1,100 yen deposit that is refunded if you return the bike to the same terminal (or forfeited for one-way drops). E-bikes are available for about 4,000 yen per day and are worth considering if you are not a regular cyclist — the bridge approaches are gentle but relentless, and e-bikes make the whole experience more relaxing. Reserve e-bikes in advance during September weekends, as supply is limited.
Terminals typically open at 8:00 AM. Advance reservation through the official website is strongly recommended for September weekends and holidays. Bring your passport for the rental process.
September: Why It Is the Best Month
July and August on the Shimanami Kaido can be punishing — temperatures above 35 degrees Celsius, intense humidity, and sun reflecting off the bridge deck. By September, the daily highs drop to a more comfortable 28-30 degrees, and the humidity eases noticeably. Morning and evening rides are genuinely pleasant, and the risk of heatstroke drops sharply.
September also brings what locals call the most beautiful light of the year to the Seto Inland Sea. The summer haze clears, and the contrast between the blue water, green islands, and white bridges becomes sharper. Sunsets from the bridges in September are legendary — long, slow fades through orange and pink that turn the entire seascape into a painting.
The school summer holiday ends on August 31, so September weekdays are notably quieter. You will share the cycling path with far fewer riders, and island accommodations are easier to book. The one caveat: September is typhoon season, so check the forecast before committing to a date. When the weather is clear, though, there is no better time.
Getting There and Away
Most riders start from Onomichi, which is easier to reach and has more atmosphere as a starting point. From Hiroshima, JR trains reach Onomichi in about 90 minutes (covered by Japan Rail Pass). From Osaka, the Shinkansen to Fukuyama plus a local train takes about two hours total.
The ride traditionally starts with a short ferry from Onomichi port to Mukaishima (the first island), since there is no cycling bridge for the first channel. Ferries run frequently and cost just 110 yen.
From Imabari at the other end, buses connect to Matsuyama (about 90 minutes), where you can catch trains or flights back. The Sunrise Itoyama terminal in Imabari is about 15 minutes by bus from Imabari Station.
If you do not want to ride the full route, express buses run between Onomichi and Imabari along the expressway, stopping at several islands. This lets you ride a partial route and bus back.
What to Eat Along the Way
The Seto Inland Sea islands are citrus country. Ikuchijima grows some of Japan's finest lemons, and you will find lemon everything — lemon gelato, lemon ramen, lemon cakes, lemon soda. The intensity of the flavors, from fruit ripened in the maritime sun, is startling.
Seafood is the other pillar. Tai (sea bream) is the local specialty — grilled, sashimi, or as tai-meshi (mixed into rice). Small harbor-front restaurants on Innoshima and Omishima serve whatever was caught that morning. Octopus from the strait is famous for its firm texture, a result of the powerful currents.
On Omishima, look for mikan (mandarin orange) soft cream at roadside stands — a simple pleasure that tastes extraordinary after a morning of riding.
Practical Tips
Bring water and sunscreen even in September — you are exposed on the bridges with no shade. Convenience stores are available on each island but not always near the cycling path.
The route is well-signed with a blue line painted on the road surface. Follow the blue line and you will not get lost. Signs are bilingual (Japanese and English).
Bridge tolls for cyclists were abolished in 2024, making the route completely free to ride.
Luggage forwarding services can ship your bags from Onomichi to Imabari (or vice versa) for around 2,000 yen. This lets you ride with just a daypack.
For overnight stays, Setoda on Ikuchijima has the most options, including a stylish hotel (Azumi Setoda, a converted traditional merchant house) and several minshuku (family-run guesthouses). Book ahead for September weekends.
Image: Shimanami Kaido Expressway over the Seto Inland Sea, Ehime, CC BY-SA 3.0, via Wikimedia Commons
