JFS Newsletter No.26 (October 2004)
http://www.japanfs.org/en/mailmagazine/newsletter/pages/027786.html

Japanese people have worshipped at Jingu Shrine, located in Ise City, Mie Prefecture, for two thousand years. Sometimes called "Ise Jingu (Ise Shrine)," it is also simply called "Jingu (the Shrine)," an indication of its pre-eminence. Ise Jingu consists of two parts, Naiku and Geku: Naiku (the Inner Shrine) is dedicated to Amaterasu Omikami, ancestral deity of the Imperial Family, and Geku (the Outer Shrine) is dedicated to the deity of food, clothing, shelter and industry.

The main sanctuary buildings of both Naiku and Geku are built in Japan's oldest architectural style, called "Yuiitsu shinmei-zukuri." Both sanctuaries are constructed using plain Japanese cypress, with a raised floor and a roof thatched with miscanthus grass and "Chigi" (forked finials) at both ends of the roof. The supporting pillars are buried into the ground.

These shrines have been re-constructed at adjacent alternate sites every twenty years without a break for the last 1,300 years; the last time was in 1993. Sacred treasures and apparel belonging to the Shrine are also renewed at this time. This ceremonial system is called the "Shikinen Sengu (or simply "Sengu") and includes various ceremonies related to rebuilding the shrines and transferring the deities from the old to the new buildings. The Sengu system plays an important role in preserving and handing down traditional crafts to the next generation, and conveying the roots of Japanese culture.

This is the only such periodic reconstruction / relocation system in Japan. It is said that the 20-year cycle was determined by Emperor Tenmu, who established the Sengu ceremony as a tradition. Thanks to this system, the ancient skills of artisans and carpenters have been passed down to the present.

The main sanctuary building follows the style of grain warehouses in the Yayoi Period (about 300 BC to 300 AD). In the past, people used these warehouses to store seed rice for next year and food in case of famines. Should these stocks run out, it would cause serious disruption, so grain warehouses were vital for protecting the people's lives.

Such a grain warehouse would be supported by more than a dozen pillars set directly in the ground and have a thatched roof. Normally a great deal of rain falls in Japan's early-summer monsoon, and as the thatched roof absorbs rainwater it becomes heavier. The heavy roof presses down on the walls, eliminating gaps between the wall boards, keeping the inside dry. The warehouse also keeps dry in summer as the roof dries out and becomes lighter, allowing air to pass through the building.

Thus, the roof and pillars function together like a living organism to securely protect the seed rice from moisture and pests.

The only way to support a thatched roof expected to increase in weight was to place the pillars directly into the ground. However, pillars set into the ground and the thatched roof eventually start to rot. Thus, the inevitable solution was to reconstruct the warehouses every 20 to 30 years. However, the life-giving seed rice could not be protected if the rebuilding started only after the old warehouses could no longer be used. Thus, periodic reconstruction of these structures probably became customary, leading to the Sengu ceremonies of Jingu Shrine in Ise, symbolizing buildings to protect life.

Next to each existing sanctuary at Naiku and Geku there is a vacant alternative site where the next rebuilding takes place. These two sites are used alternately in each Sengu ceremonial cycle. Before the Meiji Period (1868-1912), the old sanctuaries were exposed to the weather and allowed to collapse after the new ones were completed. The deities were enshrined in the new sanctuaries, while the old buildings decayed on the adjacent sites.

As many as 10,000 Japanese cypress trees are needed each time the Jingu sanctuaries of Ise are rebuilt. How have people secured so many Japanese cypress trees every 20 years?

The Jingu Shrine itself owns a large parcel of land 5,500 hectares in extent, and over 90 percent of this land is covered in forest. This forest, called the "Misoma-yama," was created as a result of learning from experience in the past. Timber was formerly taken from this forest to use for the Sengu rebuilding ceremony as well as for firewood. In the Edo Period (1603-1867), about 7 to 9 million people - about the same number as in modern times - came to worship at Jingu Shrine every year, and firewood was needed for these pilgrims, who normally stayed for a few days. As a result the local forest came to be increasingly exploited, and the timber resource depleted.

During the Edo Period, the central government (the shogunate) designated a forest in the Kiso area owned by the Owari clan in today's Nagano Prefecture for use by Jingu Shrine. However, toward the end of the Edo Period, this forest became Imperial property, and after World War II it was designated a national forest. Jingu Shrine is given priority in purchasing timber for the Sengu ceremony from this forest, but it is not the only purchaser of this rather expensive timber.

Thus it has become difficult for Jingu Shrine to depend on domestic resources for the lumber needed for the Sengu rebuilding ceremony. This possibility had been foreseen by shrine staff, however, who started taking action 80 years ago. Thinking that the shrine should have its own forest to provide timber for reconstruction, the shrine secretariat ("Jingu Shicho," part of the Interior Ministry) formed a plan during the Taisho Period (1912 - 1926) to manage the forests, and started planting trees. At the time, the nominal purpose of the project was given as landscape conservation and enhancement of the water resource recharging function of the Isuzu River, but Japanese cypresses were also planted on southern slopes.

This afforestation plan had a 200-year time-scale, and aimed to start semi-permanently supplying all the timber for the Sengu ceremony from Shrine-owned forest within 200 years. Thanks to this plan, it will be possible to obtain one-fourth of the necessary timber for the next Sengu ceremony from the Shrine lands. This proportion will increase every 20 years. Although the remainder is purchased from other domestic sources, shrine forests are now expected to provide all the timber for the reconstruction ceremonies earlier than originally planned.

The Sengu is such a large event that preparations take over eight years, four years alone just to prepare the timber. Logs are soaked in a lumber pond for two years after felling, a method known as "underwater drying," used to get extraneous oil out of the logs. After this process, the logs are stacked outside for a year for acclimatization to the severities of the four seasons. It takes another year to saw them up, and finally cover them with Japanese paper to keep them in good condition until the ceremony.

This long curing process strengthens the timber, prevents it from bending or cracking, and prepares it properly to play its part in the ceremony with its central concept of protecting life. The next question is how are the materials from the old sanctuary utilized after the ceremony?

Both the Naiku and Geku sanctuaries each have two free-standing roof-support pillars. After the Sengu ceremony, these 11-meter tall pillars are taken from the old shrines and used for another 20 years as part of two torii gates that are reconstructed on the Uji Bridge, which guards Jingu Shrine. After this 20-year period, they are again re-used to rebuild other nearby torii gates, at Shichiri-no-Watashi and Seki-no-Oiwake.

All the other parts of the old sanctuaries except these large pillars are distributed to other shrines around the country that need the lumber for their own rebuilding tasks. In a spirit of husbanding every single piece of wood, this distribution of materials following Sengu ceremonies helps maintain close relationships between Jingu Shrine and other shrines around Japan.

Two ritual events among the many that make up the Sengu ceremony process are open to the public, Okihiki and Oshiraishi-mochi. In the Okihiki ceremony, the timber is carried into the sanctuaries. In the Oshiraishi-mochi ceremony, people pick up white pebbles from the Miyagawa River for the grounds of the new sanctuary, wash them and pile them up. Then, after a purification ritual, people convey the stones to the sanctuaries in a big two-wheeled cart. Tasks are meted out to the various neighborhood associations of the local township, and the participation of many citizens make it a lively event that helps maintain the bond between the Shrine and the local people.

The next Sengu rebuilding ceremony will be the 62nd, and take place in 2013. The estimated cost will be approximately 55 billion yen, or US $0.5 billion (32.7 billion yen, or US $0.3 billion was spent on the last one, in 1993). About 60 percent of the cost will be covered by a fund maintained by Jingu Shrine for the Sengu ceremony, and the rest will be donated by the Emperor of Japan and contributed by the people of Japan.

As opposed to building long-lasting cathedrals or big stone castles, the approach of constructing a building with very simple architecture and rebuilding repeatedly was started with the idea of protecting life. This idea of giving eternity to architecture through periodic reconstruction is unusual in our world.

Japan as a nation is said to have been established during the Yayoi Period with the start of rice agriculture. Rice stocks became the people's lifeline and basis for the nation, and this spirit survives at Jingu Shrine in Ise. The custom of rebuilding the sanctuaries every 20 years has transmitted through the generations the importance of life, as well as the craftsmanship and skills to rebuild the sanctuaries. Ise's Jingu Shrine stands with dignity as the basis of the Japanese spirit, maintaining its close relationships with local people and with shrines across the country, from its two thousand-year history into an infinite future.

[For your reference]
Jingu Shrine in Ise
http://www.isejingu.or.jp/english/index.htm
Yuiitsu shinmei-zukuri
http://www.aisf.or.jp/~jaanus/deta/y/yuitsushinmeizukuri.htm
"Chigi" (forked finials)
http://www.aisf.or.jp/~jaanus/deta/c/chigi.htm