It is the oldest church within the Fortress of Babylon at Old Cairo, dating to the late seventh century. The church is famous for the cave beneath the sanctuary where the Holy Family is believed to have taken refuge during their sojourn in Egypt. A number of patriarchs were elected there.
It served as the episcopal church of the See of Misr that replaced the former See of Babylon. The Church of Sts. Sergius and Bacchus is a basilica with two rows of six monolithic columns surmounted by Corinthian capitals; some of the columns are painted with saints, probably Apostles.
The wooden screen of the altar is decorated with fine carvings representing three equestrian saints, the Nativity, and the Last Supper; they date to the 13th century. The oldest wooden altar found in Egypt (5th century) was taken from the church to the Coptic Museum.