Tarikhaneh Mosque

The Tarikhaneh Mosque ( (مسجد تاریخانهis a historic monument located on the southern limit of Damghan in Semnan province. Its name is derived from  Turkish words tari ("god") and khaneh ("home"), thus meaning "god's home". It 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 over the centuries while repeatedly being repaired. During the reconstruction of the mosque in the 18^th and 19^th century, architects set up some sharp domes instead of the original oval domes which had collapsed throughout history.

The chronology of the building's construction is not well-documented. Based on its very close similarities with earlier Sassanian architecture, it is likely from the first or second centuries of Islamic rule, possibly in the 8th century although some scholars have suggested that is overall form and style corresponds more to the 9th century.

The main plan consists of a square courtyard with 22 porches which is surrounded by arcades of barrel vaults supported by slightly pointed fired brick arches set on thick circular pillars, typical of Sassanid architecture. The pillars are 3.5 meters tall and almost 2 meters in diameter. Twenty-six of the original forty columns are still standing.

The hypostyle prayer hall consists of several naves or aisles divided by arcades and covered by vaults, with the central nave being larger than the others. It stands on 18 round columns (3 rows of 6) each with a 1.5 meter diameter. 

Unlike other large buildings paved with stones or bricks, the floor of the central courtyard has been covered just with limestone and gypsum. The original floor was unearthed during excavations to repair the outer boundaries in 2006.

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. During the Seljuq dynasty, another circular minaret was added to the building of the mosque on which a piece of Quranic quote has been carved in Kufic style. The height of the minaret is around 26 meters, including 86 steps. It was built sometime in the years 1026 to 1028 and it resembles the style of later Seljuk minarets. Although its top has fallen, but originally it must have measured more than 30 meters high, with a gallery supported on muqarnas corbels. The tower is strikingly divided into six zones of ornamentation, each rendered in brick with a different geometric pattern. An inscription at around mid-way up the tower records that its construction was commissioned by the local governor, Abu Harb Bakhtyar ibn Muhammad.

Tarikhaneh Mosque was registered as one of the national monuments of Iran on January 6, 1932.