The Yörgüç Paşa Camii was built in 1428, on initiative of Yörgüç Paşa, a Beylerbeyi (= ‘Commander of commanders’, this means: regional governor) and vizier of sultan Murat II.
The building is early-Ottoman, with a ‘reversed T’ ground plan. The prayer hall consists of two square and domed rooms, connected by a high arch. All arches are built with alternating white and red marble, which have a powerful decorative effect. The complex was restored in 1976, including the wall paintings executed in a Classical Ottoman style; this kind of paintwork is called ‘kalem işi’ (= work of the pen/paintbrush).

On the picture: The prayer room, with its mihrab and minber.

Mihrab = a semicircular niche in the wall of a mosque that indicates the direction of the Kaaba in Mecca and hence the direction that Muslims should face when praying. The wall in which a mihrab appears is the "qibla wall."
Minber = a pulpit in the mosque where the imam (prayer leader) stands to deliver sermons.

Correspondent: J.M.Criel, Antwerpen.
Source: ‘Vakıf Abideler ve eski Eserler’ - Vakıflar Genel Müdürlüğü, Ankara 1983 & Wikipedia.