Built during early centuries of the Islamic period, castles on western edge of Zagros mountain range form a chain overlooking the western passages and providing full protection for the region.

Architectural style, materials used and location of the castles are quite identical and all are made of stone and plaster. The surrounding watch towers, guard rooms, and other facilities are also similar, said Habibollah Mahmoudian, a researcher on historical castles of western Zagros.

The research on three specific castles, Shahagh, Chevar, and Kharfeh mountain protection wall reveals that the border castles constitute a barrier between the mountain and plain below and connect southern sector to the north. The passages within the region are under full surveillance of castles.

Shahagh castle in the south, Changouleh, Malek Shahi, Meymeh, Kharfeh, Esmaeel Khan Chevar, Serni castles and Kooshk castle in the Ilam province make a security belt which stretch to Yazd Gerd castle in west of the Kermanshah province.

The castles under the study are located between central plateau of Iran and Mesopotamia.