Built to protect Cairo from the Crusaders, construction under Saladin began in 1176 AD. The impressive fortress includes museums, palaces, mosques and terraces with expansive views over Cairo. Rulers of Egypt lived here for about 700 years. It is interesting to see variations in the mosque styles within the complex. Mohamed Ali mosque, also known as the Alabaster mosque, was built 1830-1848 AD and includes the tomb of Mohamed Ali. The Citadel also includes Gawhara Palace and Museum, Al-Nasir Mohammed Mosque, Suleiman Pasha Al-Khadim Mosque and several other museums.