Today is July 28, it is the day of Odaidai dance.
This dance, according to the transmission began as a ritual dance for the Mt. Fuji goddess in anger at the beginning of 9th century (quite doubtful), dedicated to her every year at the Fuji Kawaguchi Sengen jinja shrine at Yamanashi. The shrine is located at the front of Mt. Fuji, again after transmission, the place had no pyroclastic flow thank to their gardien gods: Konohanasakuya-hime*.
Every July 28th, worshippers dedicate the Odaidai dance, many offrandes to ask her her protection.
Historically it can be considered that it started during Edo period (we need confirm if another style of dance had been already practiced before Edo periode). This can be tradition of Ise school of dance. The dancers-priestess purify people and place with their ritual accessories such as sword, fans, bells, and sacred branches in paper.
Young priestess from priest's family practice 5 pieces. It is considered as special technique and transmitted secretly. During GHQ occupation, habitants protected shrines with their poor arms not to be confiscated their swords as ritual accessary.
Before the modernization, perform the dance was one of ways to earn one's living expense. In this region, only (inferior) clergy family could transmit dances (it was one of their right). They still consider this dance as secret ritual technique, the choreography either the music must not to be performed non-suitable performers (outsiders).
As a respect, I swore them not to open detail of music in public.
However, now it is 21st century, it is opened for public. While conservative worshipers considered it as secret, certain worshipers think it as a resource of tourisme. Now the Shrine gather more and more touristes thanks to their dance performance. It certainly makes conflict between habitants (worshipers).
It still reminds many hidden rituals in Japan. However, it is very difficult to access them. No explanation for publish writings about them. It is often discussed that people start to "explain" their tradition, make the "tradition", once they start to face to the outsiders (or observers). To see real tradition of their dance performance, you should reveal their secret. Once it becomes no more hidden dance, we should doubt that it is created tradition...
*According to the Kojiki myth, this princess was a god Ninigi-no-mikoto, who is ancestor of Japanese Emperor, and the very great-son of Amaterasu (Sun goddess) who decided to conquer Japan. Konohanasakuya-hime got pregnant very soon after of her mariage. Her husband doubted her. She got anger, made a ukehi ritual**; burned her maternity hut. If she safely can give birth of their divin children, it means she was faithful to her husband, if not she wasn't. What happens? Their three children were born, but she burned herself while giving birth of their last son who is the god of fire. By this episode, Konohanasakuya-hime is considered as protector from fire, especially protector from the eruption.
** Ukehi is shinto ritual to prove or make it truth your wish. You make an hypothesis, and see the result for getting god's assurance or confirmation for your wish or your action.
Exemple) You make your wish or ask, and you get god's answer as omen. I want to conquer this country. I threw this sword. If it is broken, it means god assists me to come my dream. I will conquer.
In middle age, to justify one's right, people burned sword, make people carry it from fire to sacred place. If he can, he is justified. If cannot, it means he was unfaithful to the gods, you have to pay by your life.