Spiritual Japan: Onsen Towns Along Ancient Pilgrimage Routes

Japan’s mountains have been places of spiritual practice for over a thousand years. The same volcanic activity that produces the country’s hot springs also shaped its sacred geography — peaks considered homes of gods, river valleys where Buddhist monks built forest monasteries, coastal paths walked by pilgrims seeking healing and enlightenment. Many of Japan’s most extraordinary onsen towns sit along or near these ancient routes, creating combinations of physical and spiritual renewal that are genuinely unlike anything else in the world.

The Kumano Kodo: Hot Springs and Sacred Paths

The Kumano Kodo is one of only two pilgrimage routes in the world designated a UNESCO World Heritage Site (the other is the Camino de Santiago in Spain). The routes converge on three grand shrines in the Kii Peninsula — the Kumano Sanzan — through forested mountain terrain that remains largely unchanged from medieval times.

The town of Yunomine Onsen, deep in the mountains along the Kumano Kodo, contains what is believed to be Japan’s oldest onsen — recorded in use since the 7th century. The small bath Tsuboya, a cave-like structure over a bubbling spring, is designated a UNESCO World Heritage Site in its own right. Pilgrims historically used the waters for purification before approaching the sacred shrines.

Walking sections of the Kumano Kodo and ending each day in a traditional onsen inn is one of the great slow-travel experiences available in Japan. The surrounding Wakayama and Mie countryside has significant akiya inventory for those who fall in love with the region.

Shikoku’s 88 Temple Pilgrimage and Its Onsen

The Shikoku Ohenro — the circuit of 88 temples associated with the Buddhist saint Kobo Daishi — is Japan’s most famous pilgrimage, walking or cycling approximately 1,200 km around the island of Shikoku. The route passes through or near numerous onsen towns, and the tradition of osettai — pilgrims receiving gifts and hospitality from locals — makes Shikoku one of the most open and welcoming regions in Japan for visitors and newcomers alike.

Shikoku has some of the highest vacancy rates in Japan, particularly in Kochi and Ehime prefectures. Akiya prices here reflect that — some of the most dramatic value in the country. The combination of pilgrimage culture, dramatic Pacific coastline, and abundant hot springs makes Shikoku an increasingly compelling destination for foreign residents seeking a genuinely different kind of Japanese life.

Mount Koya (Koyasan): Sacred Mountains and Forest Hot Springs

Koyasan, the mountain headquarters of Shingon Buddhism founded by Kobo Daishi in the 9th century, sits at 900 meters elevation in a forest of ancient cedar. The small town contains over 100 temple complexes, a vast cemetery where Japan’s historical figures are buried beneath moss-covered stone, and a profound atmosphere of contemplative quiet.

There are no traditional onsen in Koyasan itself (the mountain’s geology doesn’t produce hot springs), but the surrounding Wakayama countryside offers numerous options. Staying in one of Koyasan’s shukubo (temple lodgings) — waking for morning prayer service, eating Buddhist vegetarian cuisine, walking the lantern-lit cemetery at night — is an experience without equivalent.

Dewa Sanzan: The Mountains of Death and Rebirth

In Yamagata Prefecture, the three mountains of Dewa — Haguro, Gas, and Yudono — have been sites of Shugendo mountain ascetic practice for 1,400 years. The yamabushi mountain priests who train here practice rituals that include waterfall meditation, fire walking, and symbolic death and rebirth. Yudono-san, the innermost of the three mountains, is so sacred that photographs inside are forbidden.

The surrounding area around Tsuruoka and the Shonai plain has significant akiya inventory, excellent rice and seafood culture (including the famous Shonai rice and Tsuruoka, Japan’s first UNESCO Creative City of Gastronomy), and a powerful sense of living tradition. For foreigners drawn to Japan’s spiritual dimensions rather than its pop culture, this region is a revelation.

Unzen: Christian Martyrs and Volcanic Springs

Unzen in Nagasaki Prefecture is unique in Japanese history as the site where, in the 17th century, Christian converts were executed in the volcanic hot springs during the Shimabara Rebellion. Today, the area’s jigoku (hell springs) are tourist attractions, but the history gives Unzen a distinctive gravity absent from most onsen towns. The surrounding Shimabara Peninsula has extraordinary akiya values and stunning views across the bay toward Kumamoto.

Living Near a Pilgrimage Route

For foreigners considering long-term residence, proximity to a pilgrimage route offers something unexpected: a built-in community of walkers passing through, a tradition of hospitality that makes newcomers welcome, and a landscape that has been considered worth preserving for centuries. Several foreign residents along the Kumano Kodo and Shikoku routes have established guesthouses, community gardens, and cultural exchange spaces that contribute genuinely to their communities while building sustainable local lives.