This structure was initially used as a Zoroastrian Fire Temple during the Sassanid period; however, after the fall of the Sassanid Empire it was rebuilt and converted into a mosque in the 8th century. The monument is, thus, known as the oldest mosque in Iran.
Tari is the Turkic term for God, and Khaneh is a Persian word meaning house. Therefore, the compound word Tarikhaneh, translates into "the house of God".
The main plan consists of a square courtyard which is surrounded by arcades of barrel vaults supported by slightly pointed fired brick arches set on rather stumpy circular pillars, typical of the Sassanid architecture. The pillars are 3.5 meters tall and almost 2 meters in diameter.
Standing together at a distance from the mosque are the remains of a square column of uncertain date, possibly part of the original construction period, and a cylindrical minaret from the Seljuk period.
The latter was built in 1026-1029 to replace an older 9th century minaret, and is strikingly divided into six zones of ornamentation, each rendered in brick with a different geometric pattern. The minaret is 4.2 meters in diameter; its top has fallen, but originally it must have measured more the 30 meters high, with a gallery supported on muqarnas corbels.
Source: Masjed.ir