خراسان الكبرى
According to the Paikuli inscription, during the Sasanian Empire, Kashmar was part of Greater Khorasan, and the Sasanians worked hard to revive the ancient religion. It still remains a few kilometers above the ancient city of Kashmar in the castle complex of Atashgah. The ruins of this fort are now located northwest of Kashmar and are considered Sasanian monuments.