This small domed structure sits at the entrance to a gorge, with two ruined mountain fortresses southeast of the village of Bazeh Hur (located approximately 60 miles from Mashhad). H.G. Bellew (1874) & Ernst Diez (1923) were the first to identify the structure as a Sassanian fire temple, but as early as 1946 scholars published doubts about the function of this building. No evidence of a fire altar or pedestal has been found in the building, and due to its location it is considered possible that it was an outbuilding of the nearby fortresses rather than a religious monument.
The plan, with a dome sitting on four arches, is typical of a fire temple; however, with the layout of its aisles, the Bazeh Hur structure is not considered a true "chahār tāq." Two corridors remain extant, while other parts of the building are in ruins.
Due to its primitive construction and fragments of stucco found at the fortress, some scholars have suggested a Parthian (r. 247 BCE-224 CE) date, but others believe the plan and construction suggest an early Sasanian (r. 224 -651 CE) date.
Excavations on the building by archaeologists from the University of Tehran began in August 2014.
Sources:
Godard, André. The art of Iran, 182, 206. New York: Praeger, 1965.