Samurai treasures, modern luxuries: Island-hopping through Japan’s unique Seto Inland Sea

Mt. Kiro Observatory offers views over the Kurushima Kaikyo Bridge, which connects the island of Ōshima to Shikoku, the smallest of Japan's major islands. (Yusuke Ide/iStockphoto/Getty Images via CNN Newsource)

Scattered across the Seto Inland Sea, the islands of the Geiyo archipelago have long been under the radar. Until 1999, that is, when the final link of the Shimanami Kaido highway opened, connecting Japan’s main island of Honshu to the island of Shikoku, passing through six small islands.

The planners had the foresight to create a 70-kilometre (43-mile) bicycle path that runs alongside the highway and over its many bridges, a path that has since evolved to become Japan’s most popular long-distance cycling route. And thanks to the islands’ many cultural attractions, diverse dining experiences and the addition of several high-end lodging options, the area now offers a wide range of experiences for all travelers.

“While the Shimanami Kaido is internationally known for cycling, the deeper appeal of the region lies in everyday island life shaped by the Seto Inland Sea,” says Daisuke Furubayashi, who helps run the WAKKA hotel, which also has an onsite café and cycling support centre on Omishima Island.

“The sea here is characteristically calm, and the islands are home to small working fishing ports and long-established citrus farms. What often stands out to visitors is that tourism coexists with ordinary daily life.”

Located in the heart of the Geiyo Archipelago, about halfway along the highway and bike route, Omishima is the most convenient base for those wanting to spend multiple days in the islands and explore off the main drag. The island is home to several of the Shimanami route’s most iconic sites, including the spectacular Tatara Bridge.

“The islands are not theme-park destinations; they remain lived-in communities,” says Daisuke. “Beyond cycling, guests enjoy coastal walks, bridge viewpoints, small local eateries and cafés, seasonal citrus landscapes, and the slower rhythm that is increasingly rare in larger destinations.”

In search of the war god

Rising from the island’s coastal plain, trails wind through thick forest to the summit of Washigatama Mountain, Eboshi Rock and the Tateishi Observatory, with its panoramic views across the Inland Sea. The island also hosts the futuristic Toyo Ito Museum of Architecture, along with several art collections.

However, Omishima’s main claim to fame is the incredible Oyamazumi Shrine. Dedicated to the Shinto god of the mountains, sea and warfare, the complex was founded around the 7th century CE and is considered the protector shrine of all Japan. As a result, many Japanese shoguns and samurai visited the shrine to gain the war god’s approval and have their weapons blessed.

The Treasure Hall preserves many relics from those historic visits.

“Oyamazumi Shrine is home to a whopping 80 per cent of Japan’s samurai-era gear that has been designated as National Treasures or National Important Cultural Assets,” says Beth Reiber, the author of several books on Japan and an official Visit Japan Ambassador.

“Donated through the centuries by warriors wishing to express gratitude for victorious battles, it’s an astonishing collection of swords, helmets and armor, seemingly in the middle of nowhere.”

Oyamazumi also boasts a camphor tree that’s believed to be around 2,600 years old and is an officially designated Japanese national natural treasure. According to legend, anyone who circles the gnarly giant three times (while holding their breath) will have their wishes granted.

Beyond Omishima

The next island down the chain, Hakata is one of the best places to take a dip in the Inland Sea, especially at wide, sandy Hakata Beach and secluded Okiura Beach.

From there, a colossal suspension bridge leaps across a strait to Oshima Island, home to the Murakami Kaizoku Museum, which traces the archipelago’s legacy as a pirate haunt during medieval times. Also called the Murakami Suigun (“Murakami Navy”), the pirates were seagoing clans who sometimes allied themselves with terrestrial warlords. From the museum, you can peer across the bay to see the remains of a pirate castle on tiny Noshima Island.

Oshima also offers a rare opportunity for oceanfront camping along a remote stretch of sand at Tomourakume. And while it may not be traditional Japanese cuisine, nearby Setouchi Bagel offers hot and cold drinks, and freshly baked pastries, including a special Shimanami bagel flight.

Ikuchijima Island, meanwhile, is renowned for cultivating citrus. A scoop of lemon or mandarin orange sorbet at Dolce, an ice cream shop in Setoda town, is a tasty way to sample the local bounty. On the other side of town, the eclectic Kosanji Temple harbors numerous shrines and pagodas, plus an offbeat, abstract stone garden composed entirely of white marble.

“Kosanji dates only from 1936, when a local businessman erected it to honour his mother,” Reiber explains. “He spent the next three decades constructing full-scale replicas of famous Japanese temples and shrines. If you’ve ever wondered what the Hall of Dreams at Horyuji Temple in Nara looks like — or missed the chance to snap a shot of the Yomeimon Gate in Nikko — you’ll have your chance here.”

For those wanting to spend a few days on Ikuchijima, among the most recent additions at the higher end is Azumi Setoda, a contemporary ryokan that combines modern luxury with family-style hospitality.

Meanwhile, some of the archipelago’s fascinating islands that can only be reached by ferry or private boat include Osaki-Shimojima. During the Tokugawa shogunate (1603-1868), it was known for its ochaya, geisha teahouses frequented by powerful political and military figures. In more recent times, it gained fame again as a location for the Oscar-winning movie “Drive My Car” (2021).

The geisha have long since departed, but the historic Otomeza Geisha Theatre in Mitarai Town has been restored to its former brilliance. Built in 1937, it hosts a variety of traditional and cultural performances including classical music concerts, dance, drama, storytelling, seasonal festivals, heritage programs, movies and occasional geisha-style entertainment events. Vintage Japanese movie posters line the walls, while tatami mats provide seating for the performances.

The theatre is surrounded by other heritage buildings in the Townscape of Mitarai Historic Preservation Area, a fine example of small-town architecture in the mid-19th century.

“Mitarai preserves the atmosphere of a historic port town that once flourished along the Seto Inland Sea shipping routes,” says Mitsuki Ogino, executive director of Tourism Kure, which oversees the promotion of Osaki-Shimojima.

“Walking through its streets feels like stepping back in time, with beautifully preserved Edo- and Meiji-era buildings, traditional merchant houses, and scenic sea views. Unlike more crowded tourist sites, Mitarai offers a calm, authentic experience of Japan’s maritime heritage and local life.”

Mitarai has small guesthouses, traditional inns and renovated historic homes that operate as boutique accommodations, some at the high-end.

“Staying overnight is highly recommended,” Ogino adds, “because it allows visitors to experience the quiet evening atmosphere after day-trippers leave, enjoy local cuisine, and appreciate the town’s historic charm at a relaxed pace.”

Japan’s Rabbit Island

Another adventure involves taking the ferry to Okunoshima. Also called Rabbit Island, it supports a large population of very friendly feral bunnies.

Although no one knows for sure, many locals say they were let loose by Japanese pet owners or school children decades ago. But there are some who reportedly believe the rabbits were left behind when a super-secret factory on the island closed at the end of Second World War.

Visitors can learn more about the island’s dark history at the Okunoshima Poison Gas Museum and visit the ruins of the gas factory. There’s also a grassy waterfront campground, hotel, restaurant and a fine swimming beach.

Furubayashi says the Rabbit Island excursion is one of WAKKA’s most popular activities, along with guided paddleboard tours to uninhabited islands, fishing on the Inland Sea and seasonal food-related experiences like citrus and strawberry picking.

Another way to explore local waters is by joining a guided kayaking trip.

“It’s stunning!” says Miho Ogura, co-owner of Hidden Japan Travel, an outfitter that offers guided cycling and sea kayaking in Shimanami.

“Kayaking provides another perspective on this incredible location. The currents can be strong, so we always use an experienced local guide who knows the waters well. Popping in the sea for a dip while riding or resting on a deserted beach during kayaking is truly epic.

Ogura adds that while kayaking is very accessible, it still allows paddlers to visit less populated and more timeless parts of the archipelago.

“We prefer to use traditional inns, such as ryokans or minshuku. Accommodation owned by locals who have lived on the islands all their lives. You even kayak right to the hotel!”

Joe Yogerst, CNN