[4] During that time the old monastic centre dedicated to the archangel Michael was converted into a shrine to the 8th-century Muslim saint (seyyid) and warrior Battal Gazi, who allegedly fell in a battle nearby in 740.

A complex (Turkish: külliye) dedicated to Battal Gazi and containing his tomb, a mosque, a medrese, cells and ceremonial rooms for dervishes as well as charitable services for the community such as kitchens and a bakery were built in 1208 on a hill overlooking the town by Ümmühan Hatun, wife of the Seljuk sultan Gıyaseddin Keyhüsrev I and further extended in 1511 by the Ottoman sultan Bayezid II.

In August 2019, researchers headed by Prof. Murat Türkteki announced the discovery of two skeletons dating back about 5,000 years in the same sarcophagus in Early Bronze Age settlement Küllüoba.

[6][7][8] In August 2020, archaeologists headed by Prof. Murat Türktaki revealed a 5,000-year-old paint palette made of stone in the Seyitgazi district at the Küllüoba site.

[9][10] In March 2021, construction workers found a marble sarcophagus  which is 1.5 meters long and 33 centimetres wide in the Seyitgazi district at the Küllüoba site.