The foundation of the Citadel of Erzurum is not certain, but it is thought to date at least to the fifth century CE when the Byzantines founded the city of Theodosiopolis. The citadel was refurbished by the Turkish Saltukid dynasty during the twelfth century, when it received a mosque (Kale Camii) and minaret (Tepsi Minare or Saat Kulesi).
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