Most of the ancient Coptic churches are located in the Old section of the city, near the ruins of the Fortress of Babylon.
The Hanging Church:
The Hanging Church (El Muallaqa, Sitt Mariam, St Mary) derives its name from its location on top of the southern tower gate of the old Babylon fortress (in Old or Coptic Cairo) with its nave suspended above the passage.
It is the most famous Coptic Christian church in Cairo as well as the first built in Basilcan style (possibly). By the 11th century AD, it became the official residence of the Coptic patriarchs of Alexandria.
The church, which measures 23.5 meters long, 18.5 meters wide and 9.5 meters high, can be reached by steps 29 steps. It became known to travelers during the 14th and 15th centuries as the "staircase church" because of these steps, which in turn lead to an open court.
Apparently the church was originally built in a traditional basilican plan with three aisles, a narthex and tripartite sanctuary.
The main body of the current church, with its notable timber wagon-vaulted roof, features a central nave and two narrow aisles separated by eight columns on each side. Between the nave and the north aisle is a row of three columns spanned by wide lancet arches. The columns between the aisles are made of white marble, with the exception of one built of black basalt. Some of the capitals are Corinthian, and so were probably removed from older buildings.
Church of Abu Sergah (St Sergius):
Dedicated to Sergius and Bacchus, the two martyrs who died at the beginning of the 4th century, this basilica church was built in the early 5th century over the cave where the Holy Family stayed. The nave is flanked by two aisles. In the East sanctuary there are three altars and the South wall shows priceless icons. The cave and its well attract many visitors.
The original building was probably done during the 5th century. It was burned during the fire of Fustat during the reign of Marwan II around 750. It was then restored during the 8th century, and has been rebuilt and restored constantly since medieval times; however it is still considered to be a model of the early Coptic churches. Again, the most precious and ancient of the icons are on the southern wall. A vast central hall is divided into three naves by two rows of pilasters.
In much the same style as the Hanging Church, Abu Serga has 12 unique columns decorated with paintings of the Apostles. This church resembles religious structures in Constantinople and Rome. The main attraction, situated directly under the choir, is the crypt. This crypt contains the remains of the original church where tradition says the Holy Family lived. Originally this crypt was the sanctuary, but bthe crypt after the larger church was built. The crypt is closed due to flooding by water seeping in. Being tied to the Holy Family, the Church of Abu Serga continues to be a draw for Christian visitors.
Church of St. Barbarah:
Built in the 5th century to commemorate the memory of a Christian martyr. It lies in the East section of the fortress of Barbarah. It is of basilica design, with finely decorated aisles. It was rebuilt in the 10th century. But has retained its wooden door which constitutes an example of fine art.
Church of the Virgin (Church of El-Adra):
The church of El-Adra (The Virgin) is a basilica church. Built in the 8th century, it has three haykals (altars), wooden aisles inlaid with ivory and a number of rare icons.
Coptic Cathedral of Mar Morcos:
Newly built in the district of Abbassia , it is the largest cathedral in Africa and is considered a unique example of architectural evolution. The remains of St. Mark the Evangelist were transferred to the cathedral since he was the first to preach Christianity in Egypt.