Jingū, at Isë, is renewed once every twenty years. All the main jinja structures are completely rebuilt, and the sacred treasures are all duplicated, so that the new ones can be offered to the kami, primarily Amaterasu Ōmikami and Toyoukë Ōmikami. The most recent one was in 2013, so the next one is due in 2033. Formally, it is carried out on the dates set by the Tennō, and he may, in theory, choose not to have it done then, but that is extremely unlikely. The Grand Renewal (Shikinen Sengū) has historically only been delayed by war.
Although we still have sixteen years to go, the Grand Renewal is a very big job, so the preparations have already begun. In particular, the hinoki wood needed for the main buildings must be harvested, from Nagano and Gifu Prefectures in central Japan, and seasoned so that it is ready for use. The formal process begins more than six years before the climactic ceremony, but even that isn’t long enough. The harvesting of the hinoki has already started.
As this wood will be used in a particularly sacred location, it would be inappropriate to begin without some form of matsuri, although according to Jinja Shinpō the current matsuri was first performed in 1961. The ritual is performed twice, and as part of it the first tree is felled in each of the main locations that supply the Grand Renewal.
First, a standard Shinto matsuri is performed, with harae, offerings, and the reading of a norito. The norito informs the kami of the mountains that the timber will be harvested, and asks for the safety of the process and the safety of the workers and their families. Then a craftsman, in a ritual outfit, mimes striking the tree three times with an axe.
After that, six lumberjacks take turns working on the tree, to fell it using axes in a traditional technique that allows the workers to minimise damage to the tree as it falls, but which takes about forty minutes. It was traditionally used for valuable wood, which is why it is used here.
Once the tree has fallen, a small branch is taken from it and fixed in the cut stump, and everyone offers their thanks to the kami of the mountain to conclude the matsuri.