The Eight Hundred Cedar Trees of Tamawakasu Shrine

The Yao-sugi of Tamawakasumikoto Shrine: A 2,000-Year-Old Sacred Cedar of the Oki Islands

Far out in the Sea of Japan, on the volcanic island of Dōgo in the Oki archipelago, a colossal cedar tree has been quietly watching over a sacred shrine for what may be two thousand years. This is the Yao-sugi (八百スギ, literally "Eight-Hundred Cedar") of Tamawakasumikoto Shrine, designated a National Natural Monument by the Japanese government in 1929. With a trunk circumference of approximately nine meters and a base measuring some twenty meters around, this towering giant is among the most extraordinary cedar trees in all of Japan. Its presence is so commanding that visitors approaching the shrine often fall silent the moment it comes into view through the green canopy.

Standing within the precincts of Oki Province's ancient sōja (central shrine), the Yao-sugi is far more than a botanical wonder. It is woven into the spiritual landscape of the Oki Islands, the subject of beloved local legends, and a living witness to centuries of island history—from the days when emperors were exiled to these remote shores, to the modern era of the Oki UNESCO Global Geopark.

Setting: The Oki Islands and Their Sacred Heart

The Oki Islands lie roughly sixty kilometers off the coast of Shimane Prefecture in western Japan. Formed by ancient volcanic activity, this remote archipelago consists of four inhabited islands, of which Dōgo is the largest and most populated. Throughout Japanese history, the Oki Islands have occupied a special place in the national imagination. The Kojiki, Japan's oldest chronicle compiled in 712, names the Oki Islands among the very first lands created by the deities Izanagi and Izanami. In later centuries, the islands served as a place of imperial exile, most famously for Emperor Go-Toba and Emperor Go-Daigo.

Tamawakasumikoto Shrine sits in the southern part of Dōgo, near where the ancient provincial government of Oki once stood. Listed in the Engi-shiki—the early 10th-century compendium of Japanese ritual law—the shrine has long been recognized as the sōja (総社) of Oki Province, the central shrine where all the local gods of the province were jointly worshipped. The current main hall was rebuilt in 1793 in a distinctive thatched-roof style known as Oki-zukuri, and is itself designated an Important Cultural Property of Japan. The shrine has been served for generations by the Oki family, who claim descent from the ancient lords of the province.

The Tree Itself: Dimensions That Defy Belief

To stand at the foot of the Yao-sugi is to confront something that operates on a different scale of time than our own. Visitors who climb the gently sloping stone approach to the shrine, pass through the thatched zuijinmon gate, and turn to their right are met by a sight that few photographs can adequately convey.

The tree's measurements are remarkable. Its trunk circumference at chest height (the standard forestry measurement known as mokutōri) is approximately 9 meters, with some surveys recording figures closer to 9.9 meters. The base of the tree, where the great roots fan outward, measures roughly 20 meters in circumference. The cedar rises to a height of about 30 meters, though some sources give a figure as tall as 38 meters. To support its enormous spreading branches, dedicated wooden props have been placed against the lower limbs—a quiet reminder of the care required to keep such an ancient being alive.

Estimates of the tree's age vary considerably. The official information board at the shrine cites an age of more than one thousand years, while many local accounts and tourism sources speak of two thousand years or more. Whichever figure is correct, the Yao-sugi was already an old tree when the warlords of the Sengoku era walked the earth, and a young sapling somewhere around the time the Roman Empire reached its zenith.

Why a National Natural Monument? The Significance of the Designation

The Yao-sugi was registered as a National Natural Monument on December 17, 1929, under Japan's Cultural Properties Protection Law framework. The official record by what is now the Agency for Cultural Affairs notes simply that this is "one of the foremost giant cedar trees, with a trunk circumference of nine meters at chest height." Behind those terse words lies a deep recognition of botanical and cultural value.

The Natural Monument designation in Japan protects animals, plants, and geological features of exceptional scientific or cultural importance. For ancient trees such as the Yao-sugi, the designation acknowledges several intertwined values. Botanically, a cedar of this size and age represents an irreplaceable record of how the species (Cryptomeria japonica) can develop in the specific climate and soil conditions of the Oki Islands. Culturally, the tree is inseparable from the religious life of Tamawakasumikoto Shrine and from the folklore of the local community. Historically, it stands as a living monument to the antiquity of the shrine itself, predating the present main hall by many centuries.

The designation also placed the tree under formal protective measures, ensuring that its surroundings are managed with care and that any work affecting the tree is subject to consultation with cultural property authorities.

Legends That Live in the Wood

For all its scientific interest, the Yao-sugi is most beloved for the stories told about it. Two legends, in particular, have shaped how generations of islanders and pilgrims have approached this tree.

Highlights and Things to Experience

A visit to the Yao-sugi is best appreciated as part of a wider exploration of the shrine grounds and the surrounding cultural landscape. Within a few minutes' walk of the tree, visitors can encounter several treasures of national importance.

• The main hall (honden) of Tamawakasumikoto Shrine, built in 1793 in the unique thatched Oki-zukuri style, is itself an Important Cultural Property of Japan.
• The thatched zuijinmon gate, through which one passes to reach the Yao-sugi, was rebuilt in 1852 and is also an Important Cultural Property.
• The Oki Family Residence (Okinoke Jūtaku) adjacent to the shrine is a representative example of Oki's traditional large-scale shrine-priest dwellings, with features such as a Shinto altar room and a misogi-beya (purification chamber).
• The Oki Family Treasure Hall displays national treasures including the ekirei (post bells) of Oki Province—post-station bells distributed under the 7th-century Taika Reform system, of which only two extant examples are known—and the Oki provincial seal.
• Behind the shrine on a small hill stands a kofun-period burial mound, a reminder that this site was sacred long before the present shrine was built.

Many visitors describe a distinct atmosphere on the shrine grounds—a stillness particular to old places where many generations have prayed. The Yao-sugi is widely regarded as one of the most powerful "power spots" of the Oki Islands.

The Goreie Furyū Festival: A Living Tradition

For most of the year, the precincts of Tamawakasumikoto Shrine are calm and contemplative places, perfect for quiet appreciation of the Yao-sugi. But on June 5 each year, the atmosphere transforms completely. This is the date of the Goreie Furyū (御霊会風流), one of the three great festivals of Dōgo and a designated intangible folk cultural property of Shimane Prefecture.

The festival's name reflects the belief that on this day, the gods of all the various districts of Oki Province ride on horseback to the sōja to gather together. The opening rite, known as the umaire shinji (horse-charging ritual), is genuinely thrilling: eight sacred horses, each led by a team of handlers, charge up the narrow stone approach path of the shrine in turn, racing past the Yao-sugi to arrive before the main hall. After the horses have arrived, additional rites—including a rice-planting ceremony and a yabusame mounted archery display—are performed. For travelers who can time their visit accordingly, the Goreie Furyū offers a rare glimpse into a living folk tradition deeply rooted in this remote island community.

Visitor Information and How to Reach the Shrine

Reaching the Yao-sugi requires a journey, but that journey is part of the reward. The Oki Islands remain comparatively uncrowded by international visitors, and arriving here feels like stepping into a quieter, older Japan.

Travelers from outside Japan typically begin their journey at Itami Airport in Osaka or Izumo Airport in Shimane, both of which offer one daily flight to Oki Global Geopark Airport on Dōgo. The Itami flight takes about an hour, the Izumo flight about thirty minutes. Alternatively, ferries and high-speed boats operated by Oki Kisen depart from Shichirui Port (in Shimane Prefecture) or Sakaiminato Port (in Tottori Prefecture). The standard ferry takes about two and a half hours; the Rainbow Jet high-speed craft makes the crossing in roughly an hour. All routes converge on Saigō Port in Okinoshima Town.

From Saigō Port, Tamawakasumikoto Shrine is approximately five minutes by car or about ten minutes by local bus. The shrine grounds are open to visitors, and a small parking area is available. The Treasure Hall offers guided tours typically held at 9:00 and 13:00, with entrance fees charged for the museum portion. Visitors interested in the Treasure Hall are encouraged to confirm opening hours in advance, as schedules can vary seasonally.

The Yao-sugi itself can be viewed freely during daylight hours. There is no charge for entering the shrine grounds. Visitors are kindly asked to refrain from touching the trunk in ways that might damage the bark and to keep to the marked paths.

Beyond the Shrine: Exploring Dōgo

The Oki Islands were designated a UNESCO Global Geopark in 2013, recognizing both their geological uniqueness and the deep relationship between the islanders and their natural environment. After visiting the Yao-sugi, travelers will find no shortage of further destinations within easy reach.

Rōsoku-jima, "Candle Island," is a slender twenty-meter rock pillar off the northwestern coast of Dōgo. At sunset, when the conditions are right, the setting sun appears to balance on the very tip of the rock, transforming the island into a colossal lit candle. This sight can only be witnessed from sightseeing boats and is one of the most photographed scenes in all of the San'in region. Shirashima Coast at the northern tip of Dōgo is itself a National Place of Scenic Beauty and Natural Monument, known for its pale-colored cliffs and sea-carved formations. Mizuwakasu Shrine, the ichinomiya of Oki Province, displays another beautiful example of Oki-zukuri architecture and is associated with the sengū-zumō, a sumo ritual held every twenty years. Dangyō Falls, set deep in a forested valley, is one of Japan's hundred selected waterfalls. Tree lovers may wish to seek out two further giants of the island: the Kabura-sugi cedar with its unusual six-trunked form, and the Chichi-sugi, the so-called "breast cedar" of Iwakura, with its many strange downward-hanging aerial roots.