The Banya Bashi Mosque is the only Muslim temple in Sofia. It was built on the initiative of Kadi Seyfullah Effendi in the third quarter of the 16th century. This mosque is a magnificent example of the single-chamber mosques built during the so-called Golden Age of Ottoman architecture and art.
The diameter of the dome and the length of the interior walls are 15 meters. In front of the mosque is an open antechamber with three pointed arches; it is covered with small hemispherical domes supported by four monolithic stone columns with stalactite capitals, which are very typical of Islamic architecture. To the right of the antechamber is the minaret, which harmonizes well with the body of the mosque. On the southwest wall is an extension, originally intended as the tomb of Kadi Seyfullah Effendi, but was later reused as a library and is now used as a service room for the mosque. The dome and the walls of the hall were painted in the 19th century.
Adjacent to the mosque was a large double bath (sifte hamam in Turkish and banya in Bulgarian), which is associated with its name.
Since 1998, the mosque has been designated an immovable cultural asset of national importance. Its care is entrusted to the District Mufti of Sofia. The building has undergone several renovations, the most recent of which was completed in 2018, and it has functioned in this form ever since.