As part of my summer Musha Shugyo this year I visited the spiritual and historical center of budo in Japan: Kashima and Katori shrines, located in Ibaragi and Chiba prefectures respectively.
Their proximity to each other is very close, about 15 mins by train. Although 400 years ago there were no trains nor cars and travel was done by foot or horse, I can easily imagine kenshi of yore walking between these shrines as part of their musha shugyo.
The areas most famous for the development of the classical martial traditions (koryu) are located, as the saying goes, in the Kanto region, “Heiho wa Togoku kara”: heiho comes from the East, referring to the Kanto area surrounding Tokyo (heiho means martial or military arts; strategy). The Kashima and Katori Shrines lie on opposite sides of the Tone River in Ibaraki and Chiba Prefectures.
There are enshrined two of the most important Shinto martial deities: Takemikazuchi no Mikoto (Kashima Jingu) and Futsunushi no Kami (Katori Jingu). They, along with the Buddhist goddess, Marishiten, serve as the patron and protective deices for many of the martial traditions. Historical records show very clearly that young warriors gathered, or were sent by their masters, for advanced training at these shrines, which became centers for the martial arts after the end of the Heian era. Eventually this led to the foundation of the oldest known formal traditions in the martial arts, the Kashima Shinto-ryu and the Katori Shinto-ryu.
As this quote states, these shrines did not only serve as centers for religious and psychological development of warriors, but were also places they could study the more physical aspects as well. Kashima in particular was noted for its training of swordsmen.