The donor and the exact date of construction of the Haci Hamza Baths are not known. It was built sometime during the fifteenth century as a double-baths (çifte hamam), consisting of adjoining men's and women's sections. The two sections are oriented at an angle to the east-west axis with a common boiler at the western end.

The smaller women's section is located to the north with entry facing east. It consists of an entrance hall / tepidarium (sogukluk) at entrance, leading to a hot room (harara) with access to a privy cell and two private washing rooms (halvet) at the rear end.

The men's section occupies the southern half the building and is entered from the south. It consists of a tall domed hall leading to the tepidarium with privy cells and a hot room at the western end. The corners of the square hot room are enclosed to form private bathing cells with eyvans placed in between. A pool occupies the center of the space. All rooms are crowned with domes raised on muqarnas squinches with the exception of the privy cells and the vaulted tepidarium of the men's section. The walls are fitted with marble seating inside the entrance hall and the bathing spaces. Construction of the baths is roughhewn stone and brick with brick tiles and glass eyes on the domes. Today, the men's section still functions as baths whereas the women's section is used for municipal storage.

Sources:

1943. Iznik:Tarih ve Müze Komitesi Yayini. Istanbul: Kenan Matbaasi.

1972. Türkiye'de Vakif Abideler ve Eski Eserler. Volume IV. Ankara: Vakiflar Genel Müdürlügü Yayinlari.

Aru, Kemal Ahmet. 1949. Türk hamamlari etüdü. Istanbul: Istanbul Matbaacilik.

Eyice, Semavi. 1988. Iznik: Tarihçesi ve Eski Eserleri (Nicaea: The History and the Monuments). Istanbul: Sanat Tarihi Arastirmalari Dergisi Yayinlari.

Yalman, Bedri. 1999. Iznik (Nicaea). Bursa: Governorship of Bursa, Provincial Directorate of Tourism.