İmrahor İlyas Bey Camii

According to the TDV Encyclopedia of Islam, this building in Yedikule is the oldest religious structure still standing in the city. It was built in the 5th century by Studios, consul in 454, and under Bayezid II it was converted into a mosque by the sultan's master of the stables, İlyas Bey, whose name it bears. In the Ottoman period it was a centre where famous calligraphers were trained. After the fire of 1782 and the earthquake of 1894 its roof collapsed in 1908, and it stood open to the sky for about a century. In 2012 it passed to the General Directorate of Foundations; restoration began in 2023 with a temporary space-frame roof, and the aim is to reopen it for worship when the work is complete.