Oushiko Jinja Shrine
This shrine dates back to around 97 CE, when a plague was sweeping across Japan. It is said that two gods appeared to the then-emperor Keiko (25–130 CE) in a dream, telling him to build a sanctuary dedicated to the Ishi no Hoden (Stone Treasure Hall), which is an enormous rock that is 5.7 meters high, 6.4 meters wide, 7.2 meters thick, and weighs about 453,000 kilograms.
The monolith rises out of a cavity in the bedrock on three sides and one of the sides has a triangular prism protrusion. It has a pond at its base and sits on a pillar that is out of sight, so that the rock appears to be floating. Traditionally, it was thought to be divine due to its distinctive appearance and unusual position, and was also called Uki-ishi (Celestial Floating Stone). It is the shrine’s principal object of worship (shintai).
The main shrine is a wooden building with a nagare-zukuri-style (asymmetrical gabled) roof. It was erected in 1844. After the building burned down in 1807, its cypress-bark roof was rebuilt; in 1979, the cypress bark was replaced with copper shingles.
The maiden (dance hall) or maeden (front hall) is a wooden structure with an irimoya-style (hip-and-gable) roof. It is thought to have been built in the mid-nineteenth century. It also burned down in 1807 and was later rebuilt. Today it is used as the shrine’s office.
The ema-den (shrine building where votive tablets are hung) houses many sangaku (votive tablets depicting mathematical puzzles). These are said to date from the Edo period, when arithmetic enthusiasts dedicated their solutions to such puzzles, and placed them at shrines and temples around the country.