Banya Bashi mosque is an Islamic temple, which was the city of Sofia. The initiator and sponsor of the construction was made by Mulla Effendi Kady Saifullah, because of this, sometimes the mosque is also called "the Qaadi Saifullah" or "Molla Efendi" (by the way, earlier near the temple stood and the grave of Mullah). In the arch above the door you can see the stone with illegible inscription and a number 974, suggest that this designation date of construction – 974 Hijri year (1566-1567). This is one of the oldest mosques in Europe. Its name is translated into the Russian language as "a lot of baths" – the building is built over natural thermal Spa. Today Banya Bashi mosque is the only functioning Muslim temple in Sofia.

The main building of quadrangular shape, crowned by the construction of the great dome; in front is a small Central nave Annex, built in memory of late wife Effendi Kady. Above all this rises a tall minaret, from which the servant of the Church – the muezzin calls the faithful to prayer.

The mosque is a fine example of Ottoman architecture of the XVI century. Walls built of successive rows of stones and red bricks. The walls of the hall for prayers, arches and columns made of stone, the main dome is covered with plates of tin. During its long history the Church has undergone several reconstructions and its modern interior is acquired only in the 20-ies of XX century, after the restoration work financed by the Turkish Ambassador in Sofia Fethi Bey. In the middle of the century, after the war, was also carried out minor repairs. Over the last decade in the mosque installed the Underfloor heating system on private Turkish and Arab donations.

In its present state of Banya Bashi mosque can accommodate up to 1200 believers on the feast of Eid al-Adha or 700 people for Friday prayers.