Aqsunqur mosque, built in 1347 by Emir Shams ad-Din Aqsunqur, is located in Cairo's Darb al-Ahmar district. The building was renovated in 1652-1654 by Emir Ibrahim Agha al-Mustahfizan who decorated the back wall of the prayer hall, as well as his own mausoleum, with blue Iznik-style tiles, which led to the structure being known as the “Blue Mosque."