The mosque and dervish lodge (zaviye) bearing the name of Sheikh Ebu Ishak Kazeruni (d.1136) was built by Bayezid I for the dervishes of the Ishaki order in Bursa. The inscription plate (kitabe) above the door gives the restoration date of 1479 under the rule of Mehmed II.
The mosque is composed of a five-bay domed portico at entrance, leading to a domed central hall and raised eyvan on the south with vaulted ceiling over mihrab. There are two large rooms with barrel vaults to the east and west of the central hall. The dome of the central hall sits on drum ornamented with triangular planes. The portico, which appears in a state of total collapse in early photographs, has been rebuilt in the recent years.
Baykal, Kazim. Bursa ve Anitlari. Türkiye Anit Çevre Turizm Degerlerini Koruma Vakfi: 1982, Istanbul. (Edited reprint of original from 1950) .
Gabriel, Albert. Une Capitale Turque, Brousse, Bursa. Paris, E. de Boccard, 1958.
Kuran, Aptullah. The mosque in early Ottoman architecture. University of Chicago Press: Chicago, 1968