The Mosque of Sultan al-Muayyad is a Mosque in Cairo, Egypt next to Bab Zuwayla built by the Mamluk sultan Al-Muayad Sayf ad-Din Shaykh from whom it takes its name. Construction began in 1415 and the mosque was completed in 1421. It replaced a prison which was originally next to Bab Zuwayla (...) (from Wikipedia)