The Shimanami Kaido connects Imabari in Ehime to Onomichi in Hiroshima Prefecture across 70 kilometres of bridges and islands spanning the Seto Inland Sea. It is widely regarded as the world’s most scenic cycling route, and it earns that description not through superlative natural spectacle but through something quieter: a sustained sense of moving through island light over calm blue-grey water, with small fishing ports and citrus-scented hillsides at every stop. The infrastructure is excellent, the cycling paths are separated from traffic on the bridge sections, and the route rewards both the committed multi-day cyclist and the casual day-tripper.

Route Overview

The Nishiseto Expressway — the official name of the road system the Shimanami Kaido follows — runs 70 kilometres from Imabari Station in Ehime to Onomichi in Hiroshima. It crosses six islands and five suspension bridges. The cycling path is marked with blue lines on the road surface throughout, making navigation straightforward even without a dedicated map.

Total elevation gain over the full route is modest. The steepest sections are the helical access ramps spiralling up to each bridge deck, which reach approximately 6 percent gradient at their sharpest. The bridge decks themselves are flat. A fit recreational cyclist completes the full Imabari-to-Onomichi route in 6 to 8 hours of riding time. A more leisurely two-day approach — stopping to explore shrines, eat lunch at island cafes, and soak in the views — is the more satisfying option for first-time visitors.

The Six Islands

Oshima

Oshima is the first island after Imabari, reached via the Kurushima Kaikyo Bridges — actually three separate suspension bridges in sequence spanning a strait famous for its powerful tidal currents. The island itself is large and relatively quiet, with farm roads running through citrus groves and small fishing harbours. Kirosan Observatory, a short detour from the main cycling route, offers one of the best panoramic views of the Seto Inland Sea from any point along the journey.

Hakatajima

Compact and gently hilly, Hakatajima is a pleasant cycling loop if you have time for a detour. The Hakata IC Museum covers the history of the island’s fishing and salt-making industries. Most cyclists pass through on the direct route toward Omishima.

Omishima

The most culturally significant island on the route. Omishima is dominated by Oyamazumi Jinja, a Shinto shrine that predates written Japanese history. The shrine is dedicated to mountain and sea gods and has accumulated one of the most extraordinary collections of armour and weapons in Japan — donated over a thousand years by warriors who survived famous battles and wished to give thanks. The treasure house contains 80 percent of all National Treasures classified as armour and weapons in Japan. Entry ¥1,000. Plan at least an hour here.

Ikuchijima

Setoda Town on Ikuchijima is home to Kosan-ji, a temple complex built between 1936 and 1987 by Kozo Kominami, a wealthy tube manufacturer, in memory of his mother. He spent his late fortune constructing gold-leaf replicas of Japan’s most famous Buddhist and Shinto buildings — structures from Nikko, Nara, and Kyoto — and assembling them on a single hillside. The result is simultaneously strange and magnificent: architecturally serious reproductions coated in gold leaf under a warm Inland Sea sky. Entry ¥1,400. Adjacent to the temple, the Hirayama Ikuo Museum of Art houses the life work of the painter who depicted the Silk Road in large-format murals.

Innoshima

Innoshima was historically the stronghold of the Murakami Suigun, the “pirates” of the Inland Sea who controlled maritime trade and passage through these waters for several centuries. The Murakami Kaizoku Museum tells their story well. A hydrangea garden near the summit of the island peaks in late June with thousands of plants covering the hillside.

Mukaishima

The last island before Onomichi is the smallest and most densely cultivated. The route ends at the Mukaishima ferry terminal, where a short passenger and bicycle ferry (¥110, 5 minutes) crosses to Onomichi. From Onomichi the route connects to the JR San-yo Main Line for onward travel.

Oyamazumi Shrine: Worth a Dedicated Visit

Oyamazumi Jinja on Omishima deserves special emphasis. For visitors interested in Japanese history, martial culture, or Shinto, this shrine stands among the most important sites in western Japan. The national treasure armour collection represents a continuous thread of Japanese military history from the late Heian period through the Edo era, and the pieces are displayed without the crowds of Kyoto or Nara. A day trip specifically to this shrine — from either Matsuyama or Onomichi as a base — is worthwhile independent of whether you are cycling the full route.

Kosan-ji Temple in Detail

Beyond its gold-leaf architecture, Kosan-ji’s grounds include a cave passage lined with Buddhist statues, a bell tower modelled on the one at Byodo-in in Uji, and a Hill of Hope sculpture garden. The museum attached to the temple complex displays the construction photographs and Kominami’s personal correspondence, giving a sense of the peculiar ambition behind the project. It is one of those Japanese sites that makes more sense the longer you spend inside it.

Practical Cycling Information

Bicycle Rental

The primary rental option at the Imabari end is the GIANT store adjacent to Imabari Station. Road bikes rent from ¥3,000 per day; electric-assist models from ¥2,500 per day. The GIANT store in Onomichi handles rentals at the Hiroshima end. Cycle terminals at each bridge access ramp offer basic rental bicycles for ¥1,500 to ¥2,500 per day, with the option to return the bicycle at any terminal on the route.

One-way rentals incur a ¥1,100 surcharge paid at the return point. This is well worth it for cyclists doing the full route and returning by train or bus rather than cycling back.

Luggage Forwarding

A luggage forwarding service operates between the Imabari Cycle Terminal and the Onomichi Cycling Terminal, carrying bags overnight for ¥1,500 per piece. This allows cyclists to travel with a light daypack and have their main luggage waiting at the destination. Book at the cycle terminal on day one.

Staying on the Islands

Several guesthouses on Oshima and Omishima cater specifically to cyclists, offering early breakfast, bicycle storage, and drying facilities for wet gear. Reservations during April-May and October-November fill quickly. The Nishiseto tourist association website lists registered accommodation along the route.

Getting There and Return Journey

JR from Matsuyama Station to Imabari: Yosan Line limited express, 40 minutes, ¥840.

For the return from Onomichi: JR San-yo Main Line to Hiroshima (30 minutes, ¥910), then shinkansen or direct highway bus back to Matsuyama (approximately 3 hours by bus, ¥3,900). Alternatively, Onomichi connects by ferry to Setoda on Ikuchijima, allowing a partially marine return journey.

Best Seasons

Spring (April to May) offers warm, clear weather with occasional sea mist in the mornings and citrus blossoms scenting the island roads. Autumn (October to November) brings cooler cycling temperatures, clearer skies, and the light turning golden over the water in late afternoon. Summer (July to August) is hot and humid; start early and carry extra water. Winter is quiet but can be cold and windy on the bridge decks.