Shikoku

Category: Geography Key figures: Kukai (Kobo Daishi), Chosokabe Motochika

Summary

Shikoku is Japan’s smallest main island and one of the four primary landmasses, lying south of Honshu and northeast of Kyushu, separated by the Seto Inland Sea to the north and the Kii Channel to the east. With an area of approximately 18,803 square kilometers—roughly the size of Wales or the state of New Jersey—and a population of around 3.7 million (2020 census), it is the least populous of Japan’s four main islands. The island encompasses four prefectures: Kagawa (north, facing the Seto Inland Sea), Tokushima (northeast), Ehime (northwest, facing the Bungo Channel), and Kochi (south, facing the Pacific Ocean). These four prefectures are arranged around the island’s mountainous interior spine, the Shikoku Mountain Range (Shikoku Sanchi), which peaks at Tsurugi-san (1,955 meters) and Ishizuchi-san (1,982 meters)—the highest summit in western Japan and a sacred peak in Shugendo mountain worship traditions.

The island’s principal cities—Matsuyama (Ehime, population ~509,000), Takamatsu (Kagawa, ~420,000), Tokushima (~257,000), and Kochi (~327,000)—are modest in scale compared to urban centers on Honshu or Kyushu. Shikoku’s economy has historically centered on agriculture (rice, citrus, vegetables), forestry, fishing, and traditional crafts. In the contemporary era, the island faces demographic pressures common to rural Japan, including population decline and aging; all four prefectures have experienced consistent population contraction since the 1990s. Tourism—particularly pilgrimage tourism—has become increasingly central to regional economies as authorities and communities invest in heritage preservation and visitor infrastructure.

Geography and Natural Environment

The Shikoku Mountain Range

The Shikoku Mountain Range forms an east–west spine dividing the island into a narrow northern coastal plain (the Seto Inland Sea side) and a broader, more rugged southern region facing the Pacific. This topographic division creates pronounced climatic differences: the northern coast has a mild, temperate climate moderated by the Inland Sea, while the southern (Kochi) coast receives some of the heaviest rainfall in Japan—Kochi City averages over 2,500 mm of annual precipitation, with some southern areas exceeding 3,000 mm—driven by Pacific monsoons. This heavy precipitation nourishes Japan’s most pristine river systems; the Yoshino River (Tokushima), Shimanto River (Kochi), and Niyodo River (Kochi) are renowned for their exceptional water clarity and biodiversity.

The Shimanto River, flowing 196 kilometers from the Shikoku highlands to Tosa Bay, is often described as Japan’s “last clear stream” (Nihon saigo no shimizugawa) due to the preservation of its natural watershed. The river has avoided major industrial development and retains a functioning traditional fishery for ayu (sweetfish), attracted to the natural river bed and unpolluted water. This clean-water ecosystem supports regional identity and tourism branding.

Seto Inland Sea Coast

The northern coast, particularly in Kagawa Prefecture, opens onto the Seto Inland Sea (Setonaikai), one of Japan’s most important historic waterways. Kagawa’s coastline is punctuated by numerous small islands—including Naoshima, Teshima, Inujima, and Shodoshima—which have become internationally recognized contemporary art destinations since the Setouchi Triennale launched in 2010. Naoshima hosts museums designed by architect Tadao Ando (the Benesse House Museum, Chichu Art Museum, and Lee Ufan Museum), drawing architecture and art tourists from around the world to a former copper-smelting site transformed into a cultural landmark.

Cape Ashizuri

Cape Ashizuri, at the southwestern tip of the island in Kochi Prefecture, marks the southernmost point of Shikoku and is one of the most dramatic coastal landscapes in Japan—sheer cliffs dropping 80 meters to the Pacific, topped by a lighthouse established in 1914. The cape has deep associations with the pilgrimage tradition and Buddhist legend; the 38th temple of the Shikoku pilgrimage, Kongōfuku-ji, is located here, and the cape has historically been a site where pilgrims who fell ill or grew despondent were believed to encounter Kukai’s spirit. In Japanese literary tradition, the cape carries associations of endings and departures.

The Shikoku 88-Temple Pilgrimage (Ohenro)

Origins and Kukai

Shikoku’s defining cultural and spiritual significance rests on the Kōbo Daishi Pilgrimage (Shikoku Hachiju-hakkasho Meguri), a religious circuit of 88 Buddhist temples that encircles the entire island, spanning approximately 1,200 kilometers. The pilgrimage is inseparable from the figure of Kukai (空海, 774–835 CE), a Buddhist monk born in what is now Kagawa Prefecture on the northeastern corner of Shikoku. Kukai traveled to Tang Dynasty China in 804–806 to study under the Tantric master Huiguo at Chang’an; he returned to Japan with the teachings of Esoteric Buddhism (Mikkyō), founded the Shingon school, established his monastic headquarters on Mount Koya (Wakayama Prefecture, Honshu), and became one of the most influential figures in Japanese religious history. He was posthumously granted the title Kobo Daishi (“Grand Master Who Propagated the Dharma”) by Emperor Daigo in 921 CE, nearly a century after his death.

According to Shingon tradition, Kukai did not die but entered a state of eternal meditation (nyūjō) in his mausoleum at Mount Koya in 835 CE, where he awaits Miroku (Maitreya), the Buddha of the Future. This belief—that Kukai is spiritually present and accompanies every pilgrim—is central to the pilgrimage’s devotional framework. Pilgrims walk not alone but with Kukai (dōgyō ninin), a belief expressed in the traditional white overcoats (hakui) and sedge hats (sugegasa) inscribed with this phrase.

The Circuit and Its 88 Temples

The 88 temples are divided into four zones corresponding to the four prefectures, each associated with a stage of Buddhist awakening:

• Tokushima Prefecture (Temples 1–23): Hosshin no dōjō — the stage of awakening, of forming the spiritual aspiration
• Kochi Prefecture (Temples 24–39): Shugyō no dōjō — the stage of ascetic training and discipline; this is the longest stretch (approximately 400 km), passing through Kochi’s rugged mountains and coastline
• Ehime Prefecture (Temples 40–65): Bodai no dōjō — the stage of spiritual realization
• Kagawa Prefecture (Temples 66–88): Nehan no dōjō — the stage of nirvana and completion

Temple 1, Ryōzen-ji (Tokushima), is the conventional starting point, and Temple 88, Ōkubo-ji (Kagawa), marks the formal completion—after which many pilgrims travel to Mount Koya to pay respects at Kukai’s mausoleum, the true spiritual culmination.

The temples range from intimate mountaintop hermitages accessible only by steep forest stairs (such as Temple 12, Shōsan-ji, at 938 meters elevation, nicknamed the “henro-korogashi” or “pilgrim-tumbler” for its difficulty) to grand lowland complexes near regional centers. Approximately 75,000–100,000 pilgrims complete some portion of the circuit annually; walking the complete route takes 30–60 days, while those traveling by car or bus can complete it in 10–14 days. The pilgrimage has no fixed start date and can be undertaken in any direction (though clockwise, jun-uchi, is traditional; counter-clockwise, gyaku-uchi, is believed to bring bad luck but also greater spiritual merit).

The Henro Culture and Settai

A distinctive feature of the pilgrimage culture is settai—the tradition of local residents offering food, drink, lodging, or small gifts to passing pilgrims as an act of religious merit. This custom creates a social compact between pilgrims and the communities through which they pass, maintaining a relationship between Shikoku’s residents and the pilgrimage economy that has persisted for centuries. Traditional rest points (michi no eki, or older tsuyadō and zenkonyado) provide free or low-cost accommodation for walking pilgrims, sustaining access for those without means. The practice reflects Buddhist principles of generosity (fuse) and has sociological significance as a form of communal ritual participation for non-pilgrims.

UNESCO Recognition and Contemporary Pilgrimage

Japan nominated the Shikoku pilgrimage for UNESCO Intangible Cultural Heritage status, and it was under consideration as of the early 2020s. Whether walking, cycling, driving, or traveling by bus, the pilgrimage draws participants from across Japan and internationally—with particularly notable growth in foreign pilgrims (primarily from East Asia, Europe, and North America) since the 2010s. The route has been documented by numerous foreign memoirists and has featured in works of popular non-fiction such as David Moreton’s documentary Walking the Pilgrimage and Oliver Statler’s Japanese Pilgrimage (1983).

History

Ancient and Classical Period

Shikoku’s earliest historical prominence derives from its role in ancient Japanese mythology and state formation. Awaji Island (now part of Hyogo Prefecture) just north of Shikoku features prominently in the Kojiki (712 CE) as the first island created by the gods Izanagi and Izanami, and Shikoku itself appears in these texts as the second-born island. Archaeological sites in Ehime Prefecture (particularly around Matsuyama) date to the Jōmon period (c. 14,000–300 BCE), indicating long human settlement.

During the Yayoi (c. 300 BCE–300 CE) and Kofun (c. 250–538 CE) periods, Shikoku was part of the emerging Yamato state network but remained relatively peripheral compared to the Kinai heartland. The construction of large burial mounds (kofun) in Ehime and Tokushima reflects the penetration of Yamato political influence without indicating a major power center on the island.

Warring States Period and Chosokabe Motochika

Shikoku achieved its brief moment of political unity during the Sengoku Period, when Chosokabe Motochika (1539–1599), the daimyo of the Tosa domain (Kochi Prefecture), conquered the entire island by 1585—the only warlord to unite Shikoku under a single domain. Motochika enacted significant land surveys and legal reforms in Tosa before Toyotomi Hideyoshi’s forces invaded Shikoku in 1585, compelling Motochika’s submission. Though stripped of his wider conquests and confined to Tosa, Motochika remained a significant regional figure until his death and is celebrated as a hero in Kochi Prefecture’s historical memory. See Sengoku Period.

Tosa Domain and the Meiji Restoration

Like the Satsuma domain in Kyushu, Tosa (Kochi) played a decisive role in the Meiji Restoration through the Tosa Loyalist Party and the contributions of figures including Sakamoto Ryōma (1836–1867). Ryōma, a lower-ranking samurai from Tosa, became one of the key mediators who brokered the Satchō Alliance (between Satsuma and Chōshū) that formed the anti-Tokugawa coalition. He was assassinated in Kyoto in 1867, one year before the Restoration, and has since become perhaps Japan’s most romanticized historical figure—the subject of countless novels, films, and the iconic NHK historical drama Ryōmaden (2010). Kochi Prefecture celebrates Ryōma fervently; his birthplace in Kochi City is a major heritage site.

Infrastructure and Connectivity

For most of Japan’s modern history, Shikoku’s island geography imposed significant barriers to economic integration. The island lacked fixed connections to Honshu until the late 20th century, relying entirely on ferry services. Three bridge networks now link Shikoku to Honshu across the Seto Inland Sea:

1. Seto-Ōhashi Bridge (completed April 10, 1988): The longest combined road-rail bridge in the world at the time of completion, spanning approximately 13.1 kilometers across a series of inter-island bridges, connecting Sakaide (Kagawa) to the Kojima district of Kurashiki (Okayama Prefecture, Honshu). The Seto Ōhashi carries both the JR Seto-Ōhashi Line (commuter and limited express rail) and the Seto-Chūō Expressway road. Construction cost approximately ¥1.13 trillion; the project took nine years (1979–1988). The project’s scale and engineering ambition were central to Japan’s infrastructure development policy during the high-growth era.

2. Nishiseto Expressway (“Shimanami Kaidō”) (completed 1999, fully 2006): Connecting Imabari (Ehime) to Ōshima through a chain of islands to Onomichi (Hiroshima Prefecture, Honshu), spanning approximately 70 kilometers. Uniquely, the Shimanami Kaidō incorporates dedicated cycling and pedestrian paths across every bridge—making it the first expressway in Japan accessible by bicycle and one of the world’s most celebrated cycling routes, attracting hundreds of thousands of recreational cyclists annually from Japan and internationally.

3. Naruto and Akashi–Kaikyo Bridges (via Awaji Island) (1985–1998): Connecting Tokushima (via Naruto Bridge) through Awaji Island to Kobe (Honshu). The Akashi–Kaikyo Bridge (completed 1998) is the world’s longest suspension bridge at 3,911 meters total length (central span 1,991 meters). The combined route provides the primary expressway link between Shikoku and the Osaka–Kobe metropolitan area.

These connections transformed Shikoku’s economic geography, enabling day-trip tourism, commuting to Honshu employment centers, and faster freight movement—while also contributing to population outmigration as young workers gained easier access to larger urban job markets.

Economy and Demographics

Shikoku faces the most acute demographic challenges of Japan’s main islands. All four prefectures rank among Japan’s most rapidly aging and depopulating, with Kochi Prefecture consistently among the nation’s highest in elderly population share (over 35% age 65+ as of 2020). This demographic trajectory strains local public finances, rural healthcare, and agricultural labor supply.

Agricultural productivity remains high relative to population: Ehime Prefecture is Japan’s second-largest producer of mandarin oranges (mikan), Kagawa produces the premium Sanuki udon wheat noodles that have become a regional culinary identity symbol (Kagawa is nicknamed Udon Prefecture), and Kochi has developed branded premium produce including Tosa Buntan (a large citrus variety) and organic vegetables.

Traditional industries include:

• Tosa Washi Paper (Kochi): Handmade Japanese washi paper from Kochi, a nationally designated Traditional Craft; Kochi is among Japan’s largest washi-producing regions. (The 2014 UNESCO Intangible Cultural Heritage listing “Washi: Craftsmanship of Traditional Japanese Hand-made Paper” recognized three other papers—Sekishū-banshi, Hon-minoshi, and Hosokawa-shi—rather than Tosa washi.)
• Imabari Towels (Ehime): Premium cotton towels produced in the Imabari area are recognized under Japanese geographic indication (GI) protection and are regarded as Japan’s finest in the category, competing with Turkish and Egyptian terry cloth in luxury retail.
• Tosa Cutlery and Forging (Kochi): A metalworking tradition producing agricultural tools, kitchen knives, and outdoor equipment.

Related

• Major Islands — Japan’s four main islands and the archipelago’s geographic foundation
• Kyushu — Japan’s third-largest island and southwestern neighbor across the Bungo Channel
• Hokkaido — Japan’s second-largest and northernmost island
• Heian Period — the era of Kukai and the establishment of Esoteric Buddhism
• Kamakura Period — the spread of the Buddhist schools whose devotion shaped the pilgrimage
• Sengoku Period — Chōsokabe Motochika’s brief unification of Shikoku
• Meiji Restoration — Tosa’s contribution through Sakamoto Ryōma
• Tea Ceremony — a Zen-influenced cultural practice of the same religious milieu
• Noh Theater — shared roots in Heian–Kamakura Buddhist aesthetics

Sources

• Britannica. “Shikoku.” Encyclopædia Britannica Online.
• Japan Tourism Agency. “Shikoku Region: Pilgrimage and Heritage.” Official Travel Guide.
• Statler, Oliver. Japanese Pilgrimage. William Morrow, 1983.
• Reader, Ian. Making Pilgrimages: Meaning and Practice in Shikoku. University of Hawai’i Press, 2005.
• Ministry of Land, Infrastructure, Transport and Tourism. “Shikoku Region.” Japan Government.