Gahara Prefecture

Gahara Prefecture (天原県), often referred to as simply Gahara (天原). is a fictional prefecture and the main overall setting of Kamen Rider Nio. It is the place where Saga no Mamoru first fought the great darkness, and is supposedly named due to its incredible closeness to the infamous Aokigahara (where most of the Enmi reside). It is the current home of Era Saga, the Kane Shrine, and many other important characters. Date Saga implies that the Sagas' estates lie outside of it, one of the few references to the rest of Japan in-series.