One of the optional trips we took was entitled "Spiritual Cairo Tour" and included a stop at the Ben Ezra Synagogue, El Muallaga basilica which later became a Coptic Christian Church, and The Citidel, a fortress built in the 12th century to protect Cairo from the Crusade armies, which contains the Muhammed 'Ali mosque. This photo is of the ruins of one of two Roman built towers near the synagogue.