Semnan, Iran
Coordinates: 35.697778, 53.507500
Saru Castles are two related fortifications located at 10 km in north east of the city of Semnan, Iran.
The Saru Castles are believed to be used by Arsacids, Dabuyids of Tabaristan, Buyids, and eventually by the Nizari Ismailis, who built the current castle on the site of an earlier fortification.
Saru is relatively understudied, and is a well-preserved case to study the architecture of the Ismaili castles. The Saru Castles are located at 80 km of Gerdkuh, another Ismaili castle of the Qumis region.
The northern castle, the Lesser Saru, is mostly in ruins. The southern castle, the Greater Saru (ساروی بزرگ), or simply the Saru Castle, is the main one and is relatively intact.
It is 100 m higher than the Lesser Saru.