Kolah Farangi Citadel belongs to Qajar Era and it is located in Shahid Motahhari Street, Birjand. In the past, this building has been known as Hesam-od-Dowleh Citadel, Bibi Aroos Palace, and Sarkar Citadel. Kolah Farangi Citadel is constructed as a ziggurat and it has the most complete plan and space-making on the ground floor. On this floor, the springhouse has created a center such that various entrances are opened to it from surrounding spaces of the springhouse. Of adornments used in springhouse are muqarnas, rasmibandi and karbandi. A beautiful fountain is located in the springhouse that creates a fresh atmosphere in this space. The lighting of this springhouse is provided by the dome of the building and the lighting windows. The first floor of this building, which is constructed as an octagon on the ground floor, has less space and there are only several small rooms. Three other floors of this building are constructed in a symbolic manner to complete the ziggurat form of the building. Materials used in this building are brick, clay, lime and mortar. Kolah Farangi Citadel has been registered as a national monument of Iran.