Sector 7 is a place buried deep beneath the Hōzuki Castle that serves as a prison in Kusagakure. It is known as the place where to most dangerous of criminals are kept in check. It was created after Naruto originally escaped to accommodate the more powerful prisoners and keep the peace in Kusa. This sector of the prison is accessed by taking a passageway that's location is only known by the Warden of the prison. The place is run by a Warden of it's own and is policed by a squad of hand picked Anbu from Kusa.