Mount Isurugi

Mt. Sekidō: A Sacred Mountain at the Root of the Noto Peninsula

Rising to 565 meters where Ishikawa and Toyama prefectures meet, Mt. Sekidō (Sekidōzan) once held one of the most powerful religious communities in northern Japan. At its medieval height it counted more than 360 monastic lodgings and some 3,000 monks. Today the summit holds a far quieter scene: moss-covered foundation stones, stretches of dry-laid stone wall, and two timber shrine buildings standing among tall ginkgo trees. The contrast between that vanished city of temples and the forest that has reclaimed it is what gives a visit here its particular weight.

The mountain was designated a National Historic Site on October 25, 1978, recognized as a rare and important site of worship spanning the ancient through early modern periods. The local government continues archaeological excavation across the slopes, and a portion of the site has been carefully reconstructed.

A note on the name: the official reading is "Sekidōzan," though people in the neighboring Kaga and Etchū regions have long called it "Isurugiyama." The shrine at the summit, Isurugihiko Jinja, carries that second reading in its name.

From Falling Star to Mountain of Monks

According to the mountain's founding legend, a star fell here in the distant past, became a stone, and would not stop rumbling. The Japanese word for that trembling motion gives the mountain its name. A stone known as the dōji-ishi, still kept within the shrine precinct, is identified with this account. The shrine of Isurugihiko Jinja is said to have been founded to quiet the rumbling.

Dates of origin are uncertain and the sources disagree. One tradition places the founding in the sixth year of Emperor Sujin, a semi-legendary date in the first century BCE. Another credits the monk Taichō, the figure associated with opening nearby Mt. Haku to worship, in the Yōrō era of the early 8th century. What is clearer is that once the mountain absorbed the syncretic blending of Shinto kami and Buddhist devotion that shaped medieval Japanese religion, it grew into a major center. The temple complex took the name Tenpyō-ji and, after becoming a branch of the Shingon-sect temple Kajū-ji in Kyoto, drew patronage from the capital.

The monks of Sekidō, known as the "Isurugi priests," were not only ascetics. They formed an armed force, and the mountain itself sat at a strategic point between provinces. That combination drew Sekidō into the wars of its age. During the Nanboku-chō conflict of the 14th century the community sided with the Southern Court alongside the Etchū official Nakanoin Sadakiyo, and the mountain was burned in what is remembered as the first Battle of Sekidōzan. It was rebuilt with support from the Ashikaga shogunate.

A second and more devastating burning came in 1582. Noto warriors led by Nukui Kagetaka allied with the Sekidō monks and fortified the nearby Araya stronghold along the connecting ridge. The forces of Maeda Toshiie and Sakuma Morimasa, serving Oda Nobunaga, took the fort and put the mountain to the torch again. The temple city was left in ashes.

Why the Mountain Is Protected

Sekidōzan was designated a National Historic Site under the criterion covering shrine and temple ruins, former precincts, and other remains connected to religious worship. The value recognized is unusual: rather than a single building or a defined ruin, the designation covers an entire sacred mountain whose religious life ran continuously from antiquity into the early modern era.

After the second burning, the Maeda clan undertook the mountain's revival. The whole complex was reorganized under the name Sekidōzan Tenpyō-ji, and a map drawn in 1697 records a grand layout of halls, pagodas, and monastic quarters. Under Maeda protection the mountain prospered through the Edo period. That long survival ended abruptly with the 1868 government edict separating Shinto from Buddhism, which triggered the dismantling of the Buddhist establishment here.

What remains on the ground tells that whole arc. Buildings of Isurugihiko Jinja survive with ridge tags from the Genroku era. Along eight old pilgrimage approaches, including the Ninomiya and Nagasaka routes, stand kōshin stone mounds at points called gegeba, or dismounting places, where travelers once left their horses. These markers are understood to have defined the sacred boundary of Tenpyō-ji. Foundation stones, stone Buddhas, and stelae lie scattered across the slopes, marking lodgings that no longer stand.

What to See on the Mountain

The two surviving shrine buildings repay slow attention. The main hall was built in 1653 by Maeda Toshitsune, lord of the Kaga domain, and was originally called the Ōmiya. The worship hall in front of it dates to 1701 and once served as a hall for the portable shrine. Both are designated cultural properties of Ishikawa Prefecture. They sit on a mossy terrace ringed by old ginkgo trees, a species traditionally planted around shrines because its high water content was thought to help guard the timber buildings from fire.

The most vivid sense of the lost temple city comes from the reconstructed Ōmiyabō. This lodging was the administrative heart of the mountain, the controlling office that oversaw all 360-odd lodgings, handled negotiations with the Kaga domain and the head temple in Kyoto, and managed the annual ritual calendar. After it was lost in the Meiji upheaval, the site was reused for a branch school and farmland. Excavation began in 1990, and reconstruction work, drawing on the dig results and historical documents, was completed in November 2002. Visitors can now walk through the rebuilt study and kitchen wing, the guardhouse, the Onarimon and kitchen gates, the board fencing, and the chokushibashi bridge, with the foundations of the main hall and garden visible nearby.

Near the precinct lies Iwashiga Pond, a small body of water where prayers for rain were once performed. Its water has long been believed to cure illness, and on the mountain's festival day people still carry some of it home. Edo-period documents record the pond under names connected to the Buddhist offering of sacred water.

The mountain is also valued for its natural setting. It carries one of the largest beech forests in the Noto region, and the walk between sites moves through quiet woodland rather than open ground.

Around the Mountain

The summit area forms the Sekidōzan district of the prefecturally run Noto Historical Park, laid out so that visitors can move between the scattered ruins along maintained paths, with a lawn, rest shelters, and parking. The Sekidōzan Museum nearby holds materials on the mountain's history and is a good first stop for context before walking the site.

Each year on July 7, the date held to be the death anniversary of the monk Taichō, the mountain holds its opening festival and the Mitama ritual. The day is also when visitors traditionally collect water from Iwashiga Pond.

The town of Nakanoto and the wider Nanao-Kashima area hold further heritage worth combining into a trip, and the hot-spring resort of Wakura, on the coast to the north, makes a comfortable base for exploring this part of the peninsula.