Mount Asakuma Sutra Mounds

A Mountaintop Where Heian Believers Buried Their Scriptures

In September 1959, the Ise Bay Typhoon swept across central Japan and brought down countless trees on Mt. Asama, the wooded peak that rises behind the city of Ise. As work crews cleared the fallen timber from a summit ridge called Kyōga-mine, they began turning up objects that had lain hidden for roughly eight centuries: bronze cylinders, polished mirrors incised with images of the Buddha, and rolls of hand-copied scripture sealed inside small chambers of stacked stone.

That accidental find triggered the first proper survey of a place local people had long suspected held something old. By the time the investigation closed, archaeologists had identified 43 sutra mounds along the ridge. The Agency for Cultural Affairs records the group as having roughly forty. Together they form the Asamayama Sutra Mound Group, designated a National Historic Site on 15 April 1966.

There is no grand architecture here. The site is a quiet stretch of hillside set with slender stone markers, and its significance lies underground and in the display cases of the temple below. Yet few places explain so plainly what Japanese Buddhists of the late twelfth century feared, and what they did about that fear.

What the Typhoon Brought to the Surface

Kyōga-mine had given up a clue once before. In 1894 a ceramic sutra container surfaced on the slope, carrying an inscription dated to Jōan 3 (1173). No systematic study followed, and the discovery was largely set aside for the next six decades.

The 1959 typhoon changed the picture entirely. Among the items exposed during the clearing of fallen trees in 1959 and 1960 was a bronze sutra container inscribed with the year Heiji 1 (1159), older than the ceramic vessel found in the nineteenth century. Beside it lay rolled sutras, bronze mirrors engraved with Amida Buddha, and a lidded box of pale blue-white Chinese porcelain. The volume of material finally prompted a full archaeological excavation, which mapped the burial pits across the ridge.

Dated inscriptions allowed researchers to place the burials with unusual precision. The securely datable mounds fall between Hōgen 1 (1156) and Bunji 2 (1186), a span of about thirty years, though the range of grave goods suggests activity reaching a little before and after those years. For an archaeological site, that is a remarkably tight window, and it anchors the mounds to a specific and unsettled moment in Japanese history.

Burying Scripture Against the End of an Age

To understand why anyone climbed this mountain to inter sacred texts, it helps to know the idea of mappō, the "Latter Day of the Law." Many Buddhists of the late Heian period believed the world had entered a degenerate final age in which the teaching of the historical Buddha would steadily lose its power to guide people toward enlightenment.

One response was the practice of sutra burial. A patron would commission a copy of a sacred text, most often the Lotus Sutra, place it inside a protective cylinder of bronze or ceramic, and inter it in the earth. The hope was that the scripture would survive intact until the distant future arrival of Maitreya, the Buddha to come. Buried sutras also carried more personal wishes: rebirth in paradise, and the prosperity of one's descendants.

The construction at Asama followed a consistent method. A pit was dug, its floor paved with stones, and the sutra cylinder set inside together with offerings before a large capstone sealed the chamber. The official description calls these small stone chambers built from the mountain's own rock.

What makes the Asama mounds historically significant goes beyond technique. The patrons named in the records include priests and officials of the Ise Shrines. Ise was the spiritual center of the native kami tradition, and its clergy were, in principle, kept apart from Buddhist practice. That negi-rank shrine priests were commissioning Buddhist sutra burials shows how thoroughly the two religions had intertwined by the twelfth century. The site is read today as direct evidence of shinbutsu-shūgō, the fusion of Shinto and Buddhist worship, taking place at the very doorstep of Japan's most important shrine.

The artifacts were judged extraordinary in their own right. In 1963, three years before the hillside was named a Historic Site, the excavated objects were collectively designated a National Treasure under the title "Excavated Articles from the Kyōga-mine Sutra Mounds of Ise Province." Mie Prefecture holds only a handful of National Treasures, which places these modest bronze cylinders and engraved mirrors in rare company.

What You Will See on the Ridge

Visitors expecting an active dig will find something gentler. The mounds occupy a grassy rise northwest of the main hall of Kongōshō-ji, the temple that manages the site. Once the artifacts were removed for safekeeping, donors raised stone pagodas to mark the exact points where each cache had lain, so the find spots would not be forgotten. These slim stone markers, standing among cedar and broadleaf trees, are what most people actually walk up to see.

Part of the reward is simply the setting. Kyōga-mine is the southern peak of Mt. Asama, and the ridge opens onto long views over Ise Bay and, on clear days, toward the mountains of the Kii Peninsula and the Pacific. Stand here for a moment and it becomes easy to understand why people of the Heian period considered this an auspicious place to entrust their scriptures to the earth.

To meet the buried objects themselves, continue to the treasure house of Kongōshō-ji, where the National Treasure pieces are kept. The four engraved mirrors reward unhurried looking. Three depict Amida flanked by two attendant bodhisattvas, and one shows Amida alone; two of the group portray the raigō, the moment Amida descends to welcome a believer's spirit into the Pure Land. The fine incised lines turn an everyday bronze mirror into a private icon, meant never to be seen again once the chamber was sealed.

Mt. Asama and the Temple That Guards Ise

The mound group sits within the orbit of Kongōshō-ji, a temple of the Rinzai Zen school that is worth time in its own right. Its principal image is Kokūzō Bosatsu, the bodhisattva of boundless wisdom, and the temple has long been regarded as the guardian of the kimon, the inauspicious northeastern "demon gate," of the Ise Shrines. A verse from the Ise ondo folk song held that a journey to Ise was only half a pilgrimage if the traveler did not also climb Asama.

Along the path toward the temple's inner sanctuary stands one of the more unusual sights in the region: an avenue of tall wooden stupas, some rising several meters, raised through a local memorial custom called takemairi, in which bereaved families climb the mountain to honor their dead. It is a living practice, not a relic, and it gives the summit a quietly solemn atmosphere.

Mt. Asama reaches 555 meters and makes a manageable climb for those who prefer to walk; old pilgrim trails still lead up from the foot of the mountain. Most visitors, however, arrive by the Ise-Shima Skyline, a toll road that crosses the mountain and passes close to the temple. A seasonal bus serves the route from near the Inner Shrine of Ise Jingū on weekends and holidays. Near the top, a rest area with shops and viewpoints makes a natural pause before or after exploring the mounds.